It's worth pointing out that this is the first extremely public, widely acknowledged high risk mission NASA has done in over 50 years. The Shuttle was risky, but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
According to NASA's OIG, Artemis acceptable crew mortality rate is 1 in 30. Roughly 3x riskier than the shuttle. There genuinely is a world where they don't make it back home.
I am grateful that they did. And I'm grateful that we're going to go even further. I can't wait to see what Jared's cooking up (for those who don't know, he made his own version of the Gemini program in Polaris and funded it out of pocket).
> Artemis acceptable crew mortality rate is 1 in 30.
This seems insane to me. That X decades later we accept, with all our advancements in tech, a weaker system than ever before. That if we send 30 people we _accept_ that one is possible to die.
That's the starting point? That's what we document as acceptable?
Yes, and the memories of Apollo are made rosy by hagiography. I even wrote an entire thing to explain why, https://1517.substack.com/p/1-in-30-artemis-greatness-and-ri... (yeah, shameless plug, sorry - it's more for the citations than not. You can read the standards and reports I've linked to)
But if I'm allowed to repeat myself from elsewhere in the thread and the meat of the above thing,
It's physically not possible at our current level of technology to make this "safer" due to the distances and energies involved. Even with the Commercial Cargo and Crew Program (C3P), NASA has set the acceptable mortality threshold at 1 in 270 over the entire mission and 1 in 1000 on ascent / descent. If they could set it higher by gaming the math, they would. They can't.
We're a very primitive species, and the forces involved here are genuinely new. And no, Apollo wasn't much better either, at least 10 astronauts were killed in training or burned alive, as well as (far worse, because astronauts sign up for the risk) one member of ground staff.
People love to hate the Shuttle, and it ended up being subpar / fail expectations due to the political constraints NASA was under, but the Shuttle was a genuine advance for its time – a nonsensical, economically insane advance, but still an advance. If you look at the Shuttle alternative proposals / initial proposals as well as stuff like Dynasoar and Star Raker, you'll see NASA iterating through Starship style ideas. But those were rejected due to higher up front capital investment at the time.
The Shuttle is an odd franken-turduckling, because it was designed for one mission and one mission only. And that mission never happened. That cargo bay existed to capture certain Soviet assets and deploy + task certain American space assets and then bring them back to Earth.
And that's the bit that's hard to emphasize. The fact that the Shuttle could put a satellite up there, watch it fail, then go back up, grab it, bring it back, repair it, then launch again was an insane capability.
Was the program a giant fuck up at the end? Yes. But does that mean Artemis will be safer than the Shuttle? No. That's not how the energetics, time from civilization, acceptable risk profiles etc. work out.
Adding to it - Apollo 13 was a mission where 3 men should have died, but somehow didn't. If it had happened while the LM was on the moon, you would have had the CSM lose power, and then two men on the moon would have had no way to return home.
(And for the shuttle design mission - my understanding is it was likely the ability to do a HEXAGON-style film return mission in a single orbit, before the Soviets knew what was happeneing.)
note - I can't verify any of the following, it's more - for lack of a better term - aerospace nerd fan theory at this point.
Post-collapse, people think that the Buran justification was paranoia. But based on what I've read / seen (though this is getting hard to source, so I might be just good ol' hallucinating here), they weren't entirely wrong. The subtext around that large payload bay had to do with the Soviet pursuit of systems like Fractional Orbital Bombardment System (FOBS) https://en.wikipedia.org/wiki/Fractional_Orbital_Bombardment... that weaponized space.
Again, there's a reason for those ASAT tests. There's a reason for the weird specifications set in the early 1970s for the Shuttle. And I don't think deploying a spy satellite alone is it. But this is speculation. AFAICT, nothing was put on paper.
It would have been an incendiary WW3 starting act to capture a Soviet asset. But I think it is understandable if certain people within the American blob wanted that capability at hand.
I wish I was immortal. I'd drop everything for a decade and try to find people from the time who're still alive (and some still are!) and ask them these questions directly - on the record – for posterity's sake. I suspect, we came much closer to war via space than most people think. And because we didn't, we'll eventually repeat these mistakes.
Yes, you're right. I'm not going to pretend that this is a serious proposition. There isn't a lot of evidence to support it.
For me, it's a fun conspiracy theory to engage with. I'm only doing this for the love of the game as it were. Please don't take it that seriously.
But you have to admit, it is a fun theory. A lot of the claims made by the Russians / Roscosmos are most likely false, but if you notice the article says,
> The only concrete document referred to is an intelligence memo that Defense Minister Sokolov supposedly received on February 24 about the assignment of the French astronauts. Whether such a memo really landed on his desk that day is questionable (after all, Baudry’s assignment to 51E had been publicly announced by NASA in August 1984), but the idea that the assignment raised some suspicions in Soviet circles about the objectives of the Challenger mission may not be so far-fetched. There had always been a high level of paranoia in the Soviet Union about the military potential of the Space Shuttle. Misconceptions about the military applications of the shuttle, such as the belief that it was capable of diving into the atmosphere to drop bombs over Moscow, had been a key factor in the Soviet decision to develop Buran in 1976. The Buran orbiter was a virtual carbon copy of its US counterpart in shape and dimensions, exactly to counter the perceived military threat of the Shuttle. Furthermore, a couple of developments in the Shuttle program in early 1985 may have fueled the Soviet paranoia. The Shuttle had flown its first dedicated Defense Department mission (STS-51C) in January 1985 and a controversial laser experiment in the framework of SDI was planned for the STS-51G mission in June.
Whether or not said documentation can be trusted, which bits could be taken as true v. what's just insane paranoia is something that would require more work to discount than most would think. Because, as I've said, the numbers do line up from the article,
> The least one can say is that Salyut-7, which was 13.5 meters long and had a maximum diameter of 4.15 meters, would have fit inside the Shuttle’s cargo bay, whose dimensions were 4.6 by 18 meters. In fact, after the final crewed mission to Salyut-7 in 1986, the Russians significantly raised its orbit in hopes that one day it could be retrieved by Buran, which had the same dimensions as the American shuttle.
The only people who took seriously the idea of a Shuttle FOBS were the Soviets, and frankly not even all of them; as far as I've ever seen credible evidence to substantiate, it never went much past a single position paper from the early 80s. The idea that Buran was meant as a MAD-restoring FOBS has, so far as I know, not even that much support. (If you know of primary sources, in translation or otherwise, please link them.)
Read Payne Harrison's 1989 novel Storming Intrepid, followed by NASA publication SP-4221, "The Space Shuttle Decision," from 1999. [1] The first is a pretty good depiction of what you're imagining, and the second explains why the imagination of a technothriller author is where that idea went to die. Then maybe give your head a shake. If Reagan had violated the Outer Space Treaty - via NASA of all agencies! - how do you imagine it'd have stayed secret over these forty years just past?
> If Reagan had violated the Outer Space Treaty - via NASA of all agencies! - how do you imagine it'd have stayed secret over these forty years just past?
While I have no reason to believe this particular escapade, I do expect that there are a thousand such wild stories that have remained secret. Watergate seems obvious and explosive to moderns, but at the time it could easily have gone undiscovered or unremarked. How many other similar scale plots, domestic and international, succeeded or failed without ever being surfaced into the history books? A few? Dozens? Hundreds? ¯\_(ツ)_/¯
Nice article, although I'm not so sure about this part:
> There’s a reason why there wasn’t an Apollo 18, or 19 and 20. Even though funding had been secured, an executive decision was made to kill the program early, because LoC was inevitable.
Was funding really secure? I believe that was the main sticking point; a quick search [0] seems to confirm this, and the John Young quote below backs it up: "Even if they’d had the money..." Not to say the risk wasn't a factor too of course, but it doesn't look like funding was otherwise guaranteed.
Anyway, I think what sets the risk of the Shuttle apart from Apollo is summed up nicely in one of the quotes (in reference to the Apollo program): "The awareness of risk led to intense focus on reducing risk." In the Apollo program, there was a pattern of rigorously hunting down and eliminating any possible known risks, leaving unknowns as the primary source of risk; on the other hand, the Shuttle program let known risks accumulate continuously until crews paid the price for a bad draw.
When debris hit Atlantis on STS-27 [1] and the shuttle only survived on a one in a million stroke of luck -- the completely broken tile happened to be over an aluminum mounting plate -- it should have been taken as a free lesson on one more known source of risk to eliminate. Instead, it led to seven people dying completely preventable and unnecessary deaths a few years later.
Spaceflight is inherently risky, it's true. That's why things like the Orion heat shield are so worrisome; because it is physically possible at our current level of technology to make it safer, and yet for political / funding / etc. reasons we're not doing the best we can.
So there were 3 Saturn V already assembled and in existence.
Did the CSMs and LEMs exist? CSMs had a similar serial number scheme. And they designated "Block 1" and "Block 2" (iterations of the spacecraft design based on testing) CSM-0## and CSM-1##
The CSM used in Apollo 17 was CSM-114. On wikipedia it says that CSM-115 and CSM-115a were never fully assembled and cancelled, but if you look past that, you can also see that Skylab used, CSM-116, CSM-117 and CSM-118. These were Apollo CSMs, fresh off the same assembly line. https://en.wikipedia.org/wiki/Apollo_command_and_service_mod...
So there were 3 CSMs.
What about LEM? Similar number scheme, LM-## which is incremented with each one made. So first one was LM-1 and the last one used on Apollo 17 was LM-12. LM-13 is on display in a museum. LM-14 was on the production line (along with LM-15??) and a "stop work" order was issued and they were scrapped. Yes, they were literally broken down and turned into scrap. https://www.businessinsider.com/nasa-lunar-modules-lm14-lm15...
So NASA had 1 LEM and 2 were on the way. I think, we can charitably say that there were 3 LEMs available at the time. I think it's fair to say that...
So the Saturn Vs existed and had been paid for. The CSMs existed and had been paid for. The LMs existed / were on the line and had been paid for. The crews existed (and had been partially paid for).
So what is the "funding shortfall" that caused America to stop going to the moon?
The "funding shortfall" here is the money required to pay for the ground crews and personnel for carrying out the mission. And that amount was $42.1 million out of $956 million for Apollo. The total NASA budget was, $3.27 billion that year.
> NASA was canceling Apollo missions 15 and 19 because of congressional cuts in FY 1971 NASA appropriations, Administrator Thomas O. Paine announced in a Washington news conference. Remaining missions would be designated Apollo 14 through 17. The Apollo budget would be reduced by $42.1 million, to $914.4 million - within total NASA $3.27 billion.
$42.1 million. NASA admin just couldn't find $42.1 million of ground staff salaries etc out of the remaining $2.3 Billion budget.
It's probably a coincidence that this happened right after Apollo 13. The decision was announced on September 2nd, 1970. Apollo 13 happened in April, 1970.
----
So yes, the funding was there. I suspect the "funding cut" argument was an attempt to save face; after the US Government (and I mean the Government, it's clear both the White House and Congress were involved) decided to cut the cord post-Apollo 13.
I also suspect this is one of the many "open secrets" lost to time. It might have been known by "everyone" in the know at the time, but those who knew died off, and history crystallized around the written page.
We can look at what NASA did after the Columbia disaster; namely, redesign the external tank, employ stricter quality control of the foam across the board, better monitoring of the heat shield integrity, and adding contingencies for being stuck in space with a damaged shuttle.
- They replaced the specific foam insulation that struck Columbia with external heaters, and redesigned other areas where foam was necessary to ensure greater structural stability + minimize damage to the shuttle in case of breakage. They also began more thorough inspection of any heat shield panels that would be reused between missions
- They added various cameras, both on the shuttle and on the ground, to monitor the heat shield throughout launch, plus accelerometers and temperature sensors. Also, the heat shield was checked manually on every mission once in orbit for damage, both with an extension to the Canadarm, and with ISS cameras when possible (a funky maneuver [0] where they would do a backflip to flash the shuttle's belly at the ISS for it to take high res pictures)
- Every mission from then on had a backup plan in case the shuttle wasn't in a state to return to Earth (this wasn't really the case before then, which is kinda wild). Another shuttle was always ready to launch, with a new configuration of seats to allow for sufficient crew space
- They sent up equipment and materials for repairs in space with every launch, though admittedly the usefulness of that was dubious and the repair kits were never used
Perhaps 'eliminate' was too strong a word, but there's no reason these precautions couldn't or shouldn't have been taken before it resulted in deaths and the loss of a spacecraft. (well, other than the aforementioned funding/politics/organizational failure)
>Every mission from then on had a backup plan in case the shuttle wasn't in a state to return to Earth (this wasn't really the case before then, which is kinda wild). Another shuttle was always ready to launch, with a new configuration of seats to allow for sufficient crew space
Actually the backup plan almost every time was to just stay on the ISS until another Shuttle could be prepared. They only had another Shuttle on standby a couple times, during missions where they weren’t going to the ISS.
>They sent up equipment and materials for repairs in space with every launch, though admittedly the usefulness of that was dubious and the repair kits were never used
Yeah it wasn’t even useful for a situation like Columbia. It didn’t lose a few tiles or something, it had a giant hole punched into its wing.
There’s no fixing that in space. So I personally think they focused on situations they could theoretically fix, even though those situations weren’t what happened to Columbia.
Worth mentioning, this is all particularly fresh in my mind because of a recently released video by the excellent Classic Aerospace History channel on YT, "A Brief History of the Space Shuttle". It's two hours long and provides a reasonably detailed overview of the program, would recommend if you're into that sort of thing: https://www.youtube.com/watch?v=WtmOVxcga-Y
The risk couldn't have been entirely eliminated, but most likely the external tank insulation could have been modified to at least reduce the risk of chunks breaking loose and damaging the thermal tiles during launch.
Im not really convinced SLS and Artemis are best effort projects; we improve through refinement, and the only way to get there is cadence. More launches with the same general mission requirements.
One launch a year is not even close to what we can manage with our current technology, to the point where the scope is too small to be legitimately worth doing.
Its not solely a matter of energy; its about opportunity for learning. The current scale is too small to be worth doing at all.
If it was a program of something like >50 payloads over a decade, that gives enough opportunity for refinement, in cost, safety, and scale manufacture methods to actually see something new.
The value of a mission like this isn't only in the narrow technical data it returns. Its value is also institutional. Once you have an actual crewed mission orbiting the Moon, the program becomes concrete rather than aspirational. That creates momentum inside NASA and among contractors, strengthens the credibility of follow-on lunar missions, and accelerates work on the many parallel systems a sustained lunar program actually requires.
I agree entirely that it's much easier to imagine a successful moon program built around repeatable missions at high cadence, so I'm not disagreeing on that point. I would just push back on the idea that this has little or no value.
If I may be allowed one nitpick. Without fully understanding the FAA doc you link to in the article, I think it would be better to say something like loss of a plane is a 1 in a billion event for commercial airplanes. Many types of parts used in airplanes and jet engines break at much higher rates though, they just don't necessarily cause a plane loss when they do.
Wouldn’t the soviets or any other adversary prepare against letting NASA capture their satellites? You need a very small amount of C4 in the satellite to destroy the shuttle in the event of capture. Tampering with other entity‘s satellites can best be done with satellites. That also frees resources needed for bringing life support systems to orbit.
But at that point if you're building in a self-destruct for a weapon that can be so dangerous it's worth sending a shuttle to take it away from you, surely it's better to adversarially trigger the self-destruct and not bother sending the shuttle. So the C4 option might simply be a bad idea: make it more difficult and costly to remove your weapon, rather than triggering your own self-destruct.
There are easier cheaper ways of destroying a satellite than sending a space shuttle. We would have only sent a space shuttle to capture it for intelligence purposes.
Artemis certainly seems safer at least in launch. It has an escape system that could be triggered throughout launch. In comparison shuttle could not abort at all until srb separation and after that could have needed risk aerodynamic manoeuvres.
The Smithsonian article on John Young that you linked to is a good one. The only John Young quote they didn't include that I wish they had was his response to the proposal to make STS-1 an on purpose RTLS abort: "Let's not practice Russian roulette."
> It's physically not possible at our current level of technology to make this "safer" due to the distances and energies involved.
That's not true at all.
It is entirely within current technical and fiscal means to launch a much more robust and powerful craft that is capable of goign to the moon and returning with lower velocity by sending it up in pieces with Falcon 9 (Heavy) and assembling it in LEO before launching to the moon.
This mission architecture is intrinsically compromised by social constraints in the form of pork barrel spending dsfunctional decision making process.
Given current levels of technology, this would require docking with a series of space tugs. Not impossible, but Blue Origin is the only organisation working on this at a meaningful scale.
There was also Nautilus-X which never made it beyond the concept stage.
> We're a very primitive species, and the forces involved here are genuinely new.
It's absolutely wild to me that we went from inventing flying machines to putting people on the freaking moon in the span of a human lifetime. What we've accomplished with technology in the last 500 years, let alone in the last century, is nothing short of remarkable.
But, yes, in the grand scheme of things, we're still highly primitive. What's holding us back isn't our ingenuity, but our primitive instincts and propensity towards tribalism and violence. In many ways, we're not ready for the technology we invent, which should really concern us all. At the very least our leaders should have the insight to understand this, and guide humanity on a more conservative and safe path of interacting with technology. And yet we're not collectively smart enough to put those people in charge. Bonkers.
>It's physically not possible at our current level of technology to make this "safer"
Absolutely it is, if NASA was not constrained by congress to use shuttle components to build the spacecraft, they could have had double the payload mass capability at least (the Saturn V was almost twice as capable, we should be able to do a little better now). This would provide tons of extra margin for safety, and allow a shorter and thus safer route to the moon as well.
NASA certainly took many risks back then. People remember Apollo 11 for the landing, but for example on Apollo 8, with a fire roughly 2 years earlier that killed 3 astronauts, they had one manned mission (Apollo 7) and then immediately sent Apollo 8 around the moon with ONE rocket nozzle that had to work (and no LM to escape into, as the Apollo 13 astronauts had to do), basing their faith in trajectory mechanics which hadn't been tested that far out
The ejection seats on Gemini were a joke, and there's an anecdote Gene Kranz tells in his book about Gemini 9 where he thought it was too risky for them to cut away the shroud on the thing they were going to dock with (the Agena having blown up on launch) but NASA was this close to overriding him and doing it anyway (they were saved by the astronauts vetoing it, which was good because the EVA, separately, that Gene Cernan did was incredibly harrowing. he was sweating, way overworked, could barely see)
I often think about the shuttle program in relation to all these crazy complicated, wildly expensive, and incredibly fragile space telescopes we're sending to LEO or the Earth-Sun L2. Would be damn useful to be able to repair/upgrade these things like with Hubble.
Obviously I realise the shuttle program was pretty far away from being able to head out to the Earth-Sun L2(AB, and wasn't even working towards it. But man, it would be nice to have that ability.
"As of 1 April 2026, there have been five incidents in which a spacecraft in flight suffered crew fatalities, killing a total of 15 astronauts and 4 cosmonauts.[2][how?] Of these, two had reached the internationally recognized edge of space (100 km or 62mi above sea level) when or before the incident occurred, one had reached the U.S. definition of space at 266,000 ft, and one was planned to do so. In each of these accidents, the entire crew was killed. As of April 2026, a total of 791 people have flown into space and 19 of them have died in related incidents. This sets the current statistical fatality rate at 2.4 percent."
2.4% is not bad given how new this still is and how extreme the speeds and energies are.
Note that all the fatalities have been launch or landing related, not in space itself. Clawing out of this gravity well is tough. Make Earth a bit larger and you’d never get off it without something like NERVA or nuclear pulse Orion.
I wonder sometimes if that’s another thing to toss in the Fermi paradox bucket. Many rocky planets might be much more massive than Earth. On one with 3X our gravity a space program might never get going.
NERVA as envisioned had terrible thrust to weight ratio, not really usable to launch from a Super Earth. Nuclear lightbulb, orion or heck NSWR would likely work though. And bonus points for not having to think about landing systems for the return trip. ;-)
In that case aliens from a super Earth would be unable to get off it unless they decided to salt their biosphere with fissile waste. NERVA is at least contained if it works properly.
So no space program from a super Earth until they figure out not just fusion but compact high density fusion that could fly. You’d need stuff like in The Expanse, or at least in that rough ballpark.
Using fission is something they probably wouldn’t do unless they faced an existential reason forcing them to go to space, like deflecting an asteroid.
Yeah the more I learn the more I buy the rare Earth explanation.
Life may not be that unusual but it might be mostly just goo: little extremophile type bacteria and maybe very tiny creepy crawlies living in deep seas, underground, in liquid mantles in ice moons, etc.
But to get stuff even as sophisticated as frogs and bunnies, let alone something that can try space flight, requires a place that is all of: big, stable, with abundant energy, with high enough metallicity, and in an environment well shielded from flares and impacts.
I suspect that it is NOT a weaker system than before, it is more accurate about the mortality rate. In other words, there are fewer "unknown unknowns" than there were in the 60s and 80s, partially because of explosions that took out previous astronauts.
(Some would snidely say as long as they don't put seven people on the rocket they'll be fine.)
1 out of the 12 crewed Apollo missions resulted in the death of the crew, so a 1 in 12 effective mortality rate.
Apollo 13 was a very close call. If that had ended in failure the mortality rate would have been 1 in 6.
So 1 in 30 would be a pretty clear improvement from Apollo, and we are a lot better and more thorough at modeling those risks and testing systems than we were during the Apollo program.
Is 12 enough of a sample size to make a statistical judgement? What if there were 20 more which didn’t have a loss of life? Is it then 1/30? What if there were 20 more?
The risk factor is calculated _per mission_ from what I understand. You can have three accidents in a row and nothing for decades but the risk itself can still be 1 in 30.
Your point is fair and and important distinction. I think when estimating a risk factor though, this empirical data, while a low sample size, is a valuable statistic because it's empirical, and not that small of a sample size. Maybe going forward, we have 3 risk levels:
- Historical. Low N as you say. (Even though each mission and spacecraft is different and they're spread out over time, there's value in this)
- Bureaucrat number; absurdly low, but looks good to politicians etc
- Engineering estimate
If I toss a coin four times and it comes up heads three and tails once, it doesn’t mean that there’s a 75% chance that this coin lands heads up. Be careful about conflating risk factor and mortality rate.
Space is hard. If we didn’t accept these parameters we wouldn’t go to space. Apollo lost one entire crew and almost two, the Space Shuttle lost two missions where the whole crew died. The risks are real.
It honestly says something about how absurdly risk averse our society has become that an 1/30 chance of death is considered too high for a literal moonshot. You can advertise a 1/3 rate of slowly choking in vacuum and I bet you will still get a five mile long queue of people signing up for the mission.
If you want a historical comparison, over 200 men left with Magellan on his voyage around the globe and only 40 returned.
Agreed, but people were often forced into those conditions. Or were forced to make an impossible survival decision.
Were Magellan’s men volunteers? For example, in the incident with The Wager, 1,980 men left on 6 ships, and only 188 survived. Men of the original men were press-ganged (kidnapped to crew these ships), and a lot of them were even taken from an infirmary and not in great health. And, of course, conditions were pretty terrible.
So yeah, we’re more risk adverse… and also a lot better at keeping people alive. I think most people would not have signed up for some of these really risky endeavors if they knew the true risk.
Maybe we should be glad that afawct none of the people exposed to the risks of artemis ii mission were force on it against their will. I'd bet the even in The Wager you would have have some clear headed people who knew the risk and still chose it
Or the extreme casualty rates experienced by the (mostly very young) East India Company clerks in Calcutta. From Dalrymple's The Anarchy:
"Death, from disease or excess, was a commonplace, and two-thirds of the Company servants who came out never made it back – fewer still in the Company’s army, where 25 per cent of European soldiers died each year."
You're acting like if it fails they can just say "Well we said it was 1/3!" and then just get on with it. "Oops we lost a zillion taxpayer dollars and no one will mind and maybe they'll give us more money this time around!" That's just not how the world works.
Crazy indeed, glad that someone else has already mentioned Magellan, because that’s whom I also had in mind. Not sure there’s a solution for this because at this point the risk scare has been institutionalized among most if Western (and not only) society.
Crossing the Atlantic and the discovery of the Americas? How many deaths were acceptable during that initial period of exploration? That’s where we still are with space.
And the atmospheric entry is still the same as 1969. Physics doesn’t change.
A lot of advancement is multipurpose. CNCs are more accurate than machinists, computers are faster. And we have a lot of the technical knowledge written down.
Machinist never stopped working even after advanced CNCs proliferated. Humans had records of how things were made and yet new generations had to relearn it - and fail in the process.
This mission is not about sending stuff out to deep space. Its about sending out new generation of humans to deep space.
Even if you could guarantee that these new humans have exact same experience of past humans, can we guarantee that past decades simulations or theoretical knowledge acquired - while NOT actually doing something - will effectively reduce the chances of mortality?
We stopped going to the moon because it's a vanity project. It's expensive, risky, and there isn't much more science to do or that can't be done by robots.
If we got to a point where going to the Moon was significantly safer than that, we’d better start trying things even more ambitious and risky or we’ll stagnate as a species. The fatality rates for circumnavigating the globe or settling in North America or attempting to invent a working flying machine were much, much higher than that.
They could go twice the same distance, the risk would be roughly the same at that point. It's mostly the complexity and changes that make it more risky once the initial trajectory is in place.
You need a lot more impulse and more fuel to go twice as far. Probably more correction burns. A longer final burn before entering the atmosphere. So the risk of loosing the engine is much higher and probably increasing more than linear with burn time/change of impulse.
That was the fair estimate for the Shuttle program. NASA caught hell in public, justifiably, for pretending otherwise. But astronaut memoirs such as Mullane's excellent Riding Rockets paint a much more nuanced picture.
I waited until splashdown to permit my emotions to get involved, and I'm glad I did. It was really something earlier, to hear my whole neighborhood bar set up a cheer for an American mission to the Moon.
Come on! No one is forced to get on the rocket. If you don’t think it’s worth it, don’t go!
From a social perspective, I
would recommend to think of the average death per capita of an effort, which is effectively nil for Artemis (very few astronauts vs us population) compared to generating electricity with coal, which kills many annually.
The shuttle didn’t accomplish that much and didn’t get us as far as Artemis just did, the risks are well worth it. Nobody is forcing the astronauts to do their astronaut thing, imo they’re aware of the risks they’re taking, and kudos to them for that.
Eh yeah? This is frontier, pioneer stuff. We should have a greater appetite for risk as long as it’s completely transparent and the astronauts know what they’re getting into. Realistically though, there is essentially a rocket a day going up and they rarely fail anymore, so the true risk is probably much lower than 1 in 30.
Astronauts are, as a group, extremely risk loving. Every single person who signs up to go into space knows what they’re signing up for - they’ve spent their entire life working for the opportunity to be put in a tin can and shot into orbit atop a million pounds of explosives. There’s a very valid critique that NASA has become far too risk averse - we owe it to the astronauts to give them the best possible chance to complete the mission and make it back safely, but every single person who signs up for a space mission wants to take that risk, and we don’t do anyone any favors by pretending that space can be safe, that accidents are avoidable, or that the astronauts themselves don’t know what they’re signing up for. A mission that fails should not be considered a failure unless it fails because we didn’t try hard enough.
My father, who flew combat missions for the Navy in Vietnam and then became a test pilot, told me after the loss of Columbia that if he had had a chance to make that flight and spend 7 days in Earth orbit, even knowing that he'd burn up on reentry, he'd have done it.
1) Eventually you will die, no matter what. It can be the most mundane thing. Slipping on a ketchup splatter can cause great damage for example.
2) It's a profession where you intentionally kill people, so, that changes the calculation for your own risk.
3) It's a unique opportunity.
(and potentially)
4) Gives a sense of living / be in history books for his family.
So you have a possibility of a guaranteed exciting life for a death that you anyway will have, but doing something you love, it's not too bad.
> Artemis acceptable crew mortality rate is 1 in 30. Roughly 3x riskier than the shuttle
Do you have a link? I’m asking because it is very easy to make mistakes when comparing risks. For example https://news.ycombinator.com/item?id=47725961 translates that into “That if we send 30 people we _accept_ that one is possible to die.” If that interpretation is correct, given Artemis has a crew of four, that looks more like a 1:120 chance of a mortality of 4. I think that would make it an improvement over the space shuttle.
> Artemis acceptable crew mortality rate is 1 in 30.
How did they arrive at that number?
(Eg. Did they arbitrily establish the target at the outset? Or did it evolve by gauging the projected failure rate of their core mechanical etc. systems as those began to take shape, then establishing a universal minimum in line with that, to achieve some level of uniformity and avoid drastically under/over-engineering subsequent systems?)
> but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
They understood it to be extremely risky immediately. They understood the ice issue early on as evidenced by the fact that they completely changed the coating on the external fuel tank to try to compensate for it. They also added ice bridges and other features to the launch pad to try to diminish the risk. They also planned for in orbit heat shield tile repair. They specifically chose the glue to be compatible with total vacuum conditions so they could actually detach and rebond a whole tile if necessary. They developed a complicated and, unfortunately wrong, computer model to estimate the damage potential of ice strikes to the heat shield tiles. What they _finally_ came to understand was that you just have to swing the arm out on orbit and take high resolution pictures of the vehicle to properly assess it's condition.
NASA was and always is very bad at calculating systemic risk. They have the right people developing risk profiles for individual components but they've never had the understanding at the management level of how to assess them as a complete vehicle in the context of any given mission.
> Roughly 3x riskier than the shuttle.
The huge advantage they now have is a capable launch escape system which can possibly jettison them away from the rocket should any issues arise during ascent. That was the one thing the shuttle could not possibly integrate.
On the other hand they could take a far larger crew to orbit and maintain them comfortably for several weeks during the mission. The "space bus" generated a healthy 21kW from it's fuel cells and created so much water that you had to periodically dump it overboard. This was a blessing for the ISS because you could bag up all that excess water and transfer it for long term use.
Anyways.. as you can tell.. I just really loved the shuttle. It was a great vehicle that was ultimately too exceedingly tricky to manage safely.
The craft has aerodynamics and speed. It might be figuratively true "unrecoverable" but if it takes e.g. 2 weeks to complete a return, their oxygen and food and batteries ran out. Alternatively if it enters too fast they return ... in pieces.
I think you're being a pedant, if your point is a grazing entry causing rebound skip ultimately returns to some orbital path downward.
You seem to intentionally be ignoring the original quote that any error may have caused them to be flung into space. This is patently false unless the one math error is pumping in hundreds of pounds more propellant and burning far longer than the scheduled burns. NASA would need to make a significant series of mistakes beyond orbital math for the "flung out into space" statement to be true.
They certainly could've gotten the return wrong but with a perigee of 119 miles they arent even in a stable orbit and likely could deorbit themselves using only rcs thrusters at apogee, or by just waiting a few orbits.
This is underselling the risks. On top of the many trajectories which push them into unrecoverable situations, leaving them stranded in orbit, there can be trajectories where the moon gives a gravity assist strong enough to fling the spacecraft into escape velocity, fulfilling the OP.
In fact, the trajectory they chose for this mission exploited the opposite effect to yield a free return without propellant expense.
In the modern day, the chance of a math error being the root cause behind this failure mode are vanishingly small, but minor burn execution mistakes that do not require hundreds of extra pounds of propellant are definitely plausible. They were extremely common in the early days of spaceflight and plagued most of the very first moon exploration attempts. Again, with modern RCS this is unlikely. But reentry is still incredibly tight and dangerous. Apollo famously had a +-1° safe entry corridor, and Orion is way heavier and coming in even faster. If their perigee was off they could’ve easily burned up or doubled their mission time, which they may not have been able to survive.
The amount of things that would have to go wrong for the craft to get an accidental gravity boost and be ejected would be significant.
I feel like the original claim paints the whole thing as on a knife edge and barely achieved by virtue of not making a single mistake. In today's age with so many moon landing deniers and worse I feel like we should be specific about where the actual dangers challenges and unknowns there were here. In reality, the orbital mechanics are one of the simplest parts of the entire problem, at least when we're talking about a moon flyby
Yes, this is a fair point. I agree that orbital mechanics is trivially easy compared to everything else. The chances of a math mistake in particular are null, these trajectories have all been calculated years in advance.
The moon's gravity turns out to be "lumpy" because its density is not constant. This was detected by the Apollo missions and caused them to make errors in orbit calculations. This source of error could have influenced the flyby.
I’ll agree, it seems crazy that it left earth, made it to the moon, and never really left earth orbit at all. That the furthest we’ve been away is still destined to return on its own.
Watch the NASA video carefully. It's clear that, even before the "loop" begins, Artemis is slowed down and is soon going to reverse direction relative to Earth. Which of course it would anyway, as you say--because, as the video you linked to points out, it doesn't have Earth escape velocity. The TLI burn gave it just enough velocity to reach the Moon's orbit with a little extra speed left over to get it about 4000 miles further.
But what would not happen without the Moon there is the "backwards" part of the loop--the part that took Artemis around the far side of the Moon. The Moon's gravity is what did that. In the Moon-centered frame in the video, yes, it looks like just a slight deflection--because that frame is moving with the Moon, whereas Artemis was moving backwards--in the opposite direction from the Moon in the Earth-centered frame.
Without the Moon there, Artemis would never have moved backwards, relative to the Moon's orbit, at all. Its trajectory in the Earth centered frame would have been a simple ellipse, with a maximum altitude from Earth a little higher than what it actually achieved (since the Moon's gravity did pull it back a little bit).
No, it's not. You aren't responding to what I actually said. See below.
> the “free return” would have happened if they launched entirely in the wrong direction.
But it would not have been a free return that let them see the far side of the moon, which is what I said. The Moon's gravity is what made that possible. And that was very significant.
> The Shuttle was risky, but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
I think they did think of it as risky and acknowledge that it was risky, they just had a different tolerance for risk.
The Artemis mission is "more difficult" - you're firing folk way out into space and hoping you hit a fairly narrow channel where they swing around the Moon back towards you, and not just keep going straight on out beyond any hope of rescue, or biff it in hard becoming a new lunar crater. You've got to carry a lot more fuel, and a lot more technology. You're going to have them up there in a much smaller space than the Shuttle for a lot longer.
The Shuttle by contrast was kind of "proven technology" by the end of its life, and we really should have developed some new stuff off it. Columbia first flew in 1981 but "the keel was laid" as it were in 1975! Think about the massive shifts in technology between 1975 and 1981, and then maybe 1981 and 1987.
I remember someone saying in 1981 that their new car had more computer power controlling the engine than took man to the Moon (the first time round!), and my late 90s car has more computer power than took man to the Moon in the instrument cluster. Your car is probably a lot newer, and has about as much computer power as NASA had on the ground for the Apollo missions just to operate the buttons on the steering wheel that turn the radio up and down, in a chip the size of your fingernail, that costs the price of a not very good coffee.
The main failure modes of space travel have always been "we can't get the astronauts back down", "we can't get the astronauts back down at less than several times the speed of sound", or "the astronauts are now a rapidly expanding cloud of hot fried mince". What's changed is the extent to which we accept that, I guess.
I’d bet a million dollars that Orion will win every safety metric compared to the shuttle once it is retired. NASA deluded itself in thinking the Shuttle was safe. The reality is that the Shuttle was the most dangerous spaceship anyone ever built.
That's physically not possible due to the distances and energies involved. Even with the Commercial Cargo and Crew Program (C3P), NASA has set the acceptable mortality threshold at 1 in 270 over the entire mission and 1 in 1000 on ascent / descent. If they could set it higher by gaming the math, they would. They can't.
We're a very primitive species, and the forces involved here are genuinely new. And no, Apollo wasn't much better either, at least 10 astronauts were killed in training or burned alive (8 NASA, 2 sister MIL programs), as well as (far worse, because astronauts sign up for the risk) one member of ground staff.
People love to hate the Shuttle, and it ended up being subpar / fail expectations due to the political constraints NASA was under, but the Shuttle was a genuine advance for its time – a nonsensical, economically insane advance, but still an advance. If you look at the Shuttle alternative proposals / initial proposals as well as stuff like Dynasoar and Star Raker, you'll see NASA iterating through Starship style ideas. But those were rejected due to higher up front capital investment at the time.
The Shuttle is an odd franken-turduckling, because it was designed for one mission and one mission only. And that mission never happened. That cargo bay existed to capture certain Soviet assets and deploy + task certain American space assets and then bring them back to Earth.
And that's the bit that's hard to emphasize. The fact that the Shuttle could put a satellite up there, watch it fail, then go back up, grab it, bring it back, repair it, then launch again was an insane capability.
Was the program a giant fuck up at the end? Yes. But does that mean Artemis will be safer than the Shuttle? No. That's not how the energetics, time from civilization, acceptable risk profiles etc. work out.
How could a comparison between such dissimilar programs ever be meaningful? NASA flew 135 Shuttle missions over the course of 30 years; Orion will be doing well to approach a tenth of that number.
I think we are a long way along from digging out Dr Feynman to look into why a shuttle exploded.
Unless you happen to have some deep links into NASA, in which case please elucidate us all, then why not celebrate a happy and safe return from a sodding dangerous mission that involved things like >25,000 mph relative velocity and some remarkable navigation.
When you depart earth (close quarters gravity, air resistance, things in the way), everything moves really fast, really fast and any acceleration becomes an issue really ... fast!
The moon moves, the earth moves: both famously in some sort of weird dance around each other and both orbit around the sun. Obviously the moon affects the earth way less than vice versa but it still complicates things.
I think that NASA did a remarkable job of making Artemis II look almost routine and I don't think that was down to behaving as they did in the past.
> I think that NASA did a remarkable job of making Artemis II look almost routine and I don't think that was down to behaving as they did in the past.
I have been excited for Artemis--yes it's big and expensive and late, but look how it has brought out the best of what humans can be--but, despite all that, the heat shield situation was textbook "normalization of deviance." Just as the O-rings were not designed to have any damage but they retroactively justified it was okay, just as there was not supposed to be any foam or tile damage but they retroactively justified it was okay, so too was the Artemis I heat shield not supposed to come back with damage, but they...
I'm not trying to be negative, and risks are inevitable, but the resemblance to me was uncanny. The lesson with normalization of deviance is that a successful result does not inherently mean a safe decision. After all, most of the time that you play Russian Roulette you will escape unharmed.
There will always be issues on something a mad as putting some people on a firework and shooting them at a moving target 100,000 miles away from a moving platform.
The heat shield failure was a test and the result was a working heat shield, when it counted. That's the point of tests. NASA already had several working heat shields from the old missions but the new one needed testing - for the shape of the craft etc. They already had a lot of data from the old efforts (that worked).
I think that exit and re-entry are almost routine now, provided your rocket doesn't explode. The tricky bit is out there in space and trying to make the moon a resource of some sort.
The new one failed in ways it was not designed to fail. In C-compiler terms it was "undefined behavior." In Donald Rumsfeld terms it was an "unknown unknown."
The mere fact that the outcome was successful does not inherently indicate that the decision-making was safe: the O-rings "worked" for 24 missions and the foam/tiles "worked" for 111. Nevertheless there were ample warnings and close calls.
Reentry from the Moon is not routine. Re-entry speed was about 40% faster than from low earth orbit, and kinetic energy goes up by the square, so about double.
Yes, and the four RS-25 main engines on the SLS rocket (Space Launch System) are literally SSME's harvested from the shuttles (Space Shuttle Main Engine). Of course that means they are re-usable. So sad to see them plummet to the ocean floor. Perversely Rocketdyne is building cheaper non-reusable versions of the RS-25 for future missions.
Yes, Challenger - although program management knew they were violating a launch constraint (temperature), and it was the low temperature that produced the conditions necessary for SRB failure.
As with any aerospace mishap, it's a chain of events, not just one cause.
I believe what it destroyed was the strut holding the booster to the tank. When the strut burned through the assembly came apart and aerodynamic forces did the remainder of the destruction.
The Artemis SRBs incorporate design changes to address the causes of the Challenger failure. Specifically they changed the joint design, added another o-ring, and they have electric joint heaters to keep the seals warm.
I mean it's the first space crew on an anti-science mission, right?
The point of them being there isn't discovery, it's to try to discourage anyone who wants try to understand and protect the planet that we all rely on for life
As an American I feel like I've been going through a bit of an identity crisis from what I remember growing up.
Probably the rose tinted glasses of being a child but being from Florida I always had a sense of amazement and wonder as I heard the sonic boom of the shuttle returning to earth.
Really felt like I was coexisting in this incredible scientific powerhouse of a country full of bright and enabled peoples that knew how to prioritize curiosity and innovation.
Feeling like a bit of a "vibe" post which is everything wrong lately but I can't help but feel some satisfaction that we're still able to accomplish something like this in our space endeavors.
I think especially online there's a lot of emphasis on "everything is wrong". A mission like this is hard to ignore and highlights the bias. On the whole, despite setbacks, we continue.
If you want to dispel a bit more of the ever-pervasive online pessimism bias, read up on global rates of hunger the last time we flew to the moon (1972) vs now. The reality is, for all the problems we face today, there's no sane answer other than today to the question "when would you prefer to be born as a random person on earth"
A global view is probably not the right way to look at things, encouraging as it may be. Of course globally hunger rates fell and so did child mortality. If nothing else, by the inexorable progress of science and technology.
But what about comparing the same country/region? After all that's a better sense of how things are progressing locally to you, and when people are asked "are things better or worse" they probably compare the way they live with the way their parents lived.
Would you rather be born in 1980 or 2020 in China? In Poland? No question. Same question but in the USA? In the UK? The West in general? I'm really not so sure.
The '70s were not hopeful. Economy was terrible, Vietnam ended but still hung over the culture, Watergate, Three Mile Island, Iranian hostage crisis, cold war threatening to turn hot at any moment, double-digit mortgage rates.... and Disco.
Some parts of the US economy may have been terrible (perhaps due to the increased oil price, which became closer to the true cost of oil than that of the previous cheap oil, which was so cheap because it was basically stolen by USA), but in another parts of the world the economy was great in comparison with what followed after 1980.
Moreover, even in the US, the seventies were the greatest time for the electronics and computers industries, when the greatest amount of innovations have been made.
After 1980, there have been huge advances, but all of them were completely predictable, i.e. the electronics and computing industries settled on an evolution path that was well defined for a few decades, with very few surprises.
The seventies were much wilder, when much more diverse things have been tried (and many of those have failed) and they were surely hopeful, especially in their second half.
During the seventies, there were a lot of US companies that I liked and I was convinced that if I bought something from them that was mutually beneficial, because they really tried to make products that fulfilled as well as possible the needs of their customers, while ensuring a decent and reasonable profit for the vendor.
Nowadays there exists no big company in the entire world from which I can buy a product without feeling that this is an adversarial transaction, where they try as hard as they can to fool me into paying as much as possible for something that is worth as less as possible.
Definitely not the 70's. I think the most recent age that might have counted as hopeful was really between the fall of the Berlin Wall (1989) through the beginning of the GWOT (9/11/2001). So basically the 90's.
The seventies were a more representative time for technological hopes, during a time when it was not yet clear which are the right technological choices. The nineties were a time of rapid technological progress, but most of it was perfectly predictable, without surprises. The only thing that was surprising during the nineties was how important the Internet became in practice, even if the evolution of its underlying technology was not surprising.
The time correctly delimited by you was the time of the greatest false political hopes, when everybody around the World believed that we got rid of the communist blood-sucking parasites and now the World would become that which had been described for decades in the propaganda of the Voice of America, where the political elites are held accountable for their actions, so if they are bad they are replaced through democratic elections, and the bad commercial companies are eliminated by competition in the free market.
Instead of this happening, already a couple of years before 9/11 a wave of destructuring many important historical companies happened, followed by a huge wave of mergers and acquisitions that has continued until today and which has eliminated competition from most markets, so that they are now dominated by quasi monopolies. Then the democratic elections have brought to power worse and worse human beings, all of whom have been much worse than some citizens that would have been randomly selected for those positions.
Nowadays, the economies of USA and of the other "Western" countries, and also their political institutions, resemble much more those of the socialist countries that they mocked during the seventies, than those of USA and W. Europe of that time.
So all the hopes of the nineties were naive and none of them was realized.
I had to explain to my wife and kids (not that I'm in this field, but I also have to remind myself) that we are able to pinpoint where the craft will land, when it will land down to the minute, because of ... just ... math. And we're able to get them there and back because of science.
It all boils down to equations that describe the world accurately, and a way of experimentation, iteration, thinking that gets us all the way to do something this unbelievably complex.
The analogies for these things like "hitting a golf ball into a hole in one 5,000 miles away" are always fun.
I like starting from the fact that Ptolemy was able to get the accuracy of the "motions of the heavens" down so well that it took more than a thousand years to get observations that showed discrepancies. The math, it maths.
I always feel like these analogies don't really fit the real space flight as you quite often have a lot of time to correct the trajectory if you get it roughly right during launch and even that takes a couple minutes. You also have closed circuit guidance and external radar stations to verify the trajectory.
You really don't have anything like that when playing golf, so I don't thin it is a good analogy.
But for the old Sprint anti balistic missile - that was spot on. :D Hitting ICBM warheads kilometers abobe ground, second before detonation - yeah, that fits. It also dispelled the myth that you can't communicate to compact craft due to re-entry plasma. Of course you can, just use a 30 MW radar beam & it will get through just fine! Not to mention the Sprint missile was protected by an ablative heatshield and covered by plasma going up during launch. :D
There’s a big difference (not really as much as you might think because fuel is limited) between a single shot with no thrusters and a rocket that has all sorts of adjustments possible.
It’s all in fun, really, like the old analogies involving hard drive heads and jet planes.
I feel like it’s “easier” with space math because there’s so little to interfere with the course. With a golf ball, the basic math is easy, but the slightest bit of wind throws it off way beyond the acceptable error, and you can’t model all the wind perfectly.
The first-order approximations are easy. When you start adding up all the other factors, it gets complicated fast. The solar wind, which isn't constant, affects trajectories. Earth's atmosphere is neither homogenous nor perfectly predictable along many dimensions: upper-level wind speeds and directions, air density, and temperatures, to name a few. The Moon's gravitational field is very lumpy. Earth's gravitational field, while relatively smooth compared to the Moon, also isn't perfectly uniform. Propulsion systems have tolerances. Same with parachutes. The location of the vehicle's center of gravity affects everything.
All of these factors and more have to be taken into account if you want your predictions to be accurate. Aside from telemetry processing, most of the computing power on the ground during a space mission is used for churning out navigation solutions.
Fun info: The NASA orbital codes include things like photon pressure... from sunlight reflected off of other planets in the solar system. At some point, I think they are just showing off :)
We know where it will land accurately because that maths and physics has been sharpened with butt loads of data. Even the reentry blackout has links to war in Plasma Stealth[0].
That data was mostly obtained because we want to know where our ICBM warheads will land. And where the enemies ICBM warheads will land so we can work on the problem of shooting them down.
The Russian Kinzhal missile can hit targets at mach-10, with a plasma aura making it's terminal phase hard to track on Radar. But after some data was collected Patriot missile systems were able to intercept about 1 in 3 air launched Kinzhal missiles. Then minor terminal adjustments were introduced and interception fell to about 1 in 20. Now there's a constant cat and mouse game going on in Ukraine.
On the one hand that's a good thing, our combative efforts being sublimated into curiosity of the world.
On the other hand, we still put far more effort into furthering our ability to destroy the world.
IIRC reentry plasma is actually highly radar reflective - so it is not hard to track, just hard to hit due to the speed, as there is limited time to do it.
If that were the case then the mach-10 Kinzhal would be harder to hit than the mach-5 Kh-32.
But the interception rate for the Kh-32 is basically nonexistence (<1%).
The Kh-22/32 is why mach-5 + maneuverability is the current goal of offensive missile systems.
The plasma has complex interaction with radar, it's not stealth as in entirely invisible just chaotic scattering and reflections. The result is a jamming effect preventing a definite intercept solution.
On the other hand the plasma shows up on satilite based IR tracking systems.
That's an absurd statement. By your logic, you can't just say that we have the smallpox vaccine "because of Edward Jenner". Because you would also "have to prove we could not do it without Edward Jenner". What does that even mean??
Wild that they manage to fly to the moon but still seem to be having those comms problems. Asking the astronauts if they’re really pressing the PTT button is wild.
My friends and I have been deriving much amusement from the comms issues. We can fly people around the moon, talk with them, send back high res video, but talk to the boat that’s close enough to swim to? Forget about it!
i was thinking maybe astronauts can be disoriented when splashing down and that's why they figured they should ask if the right buttons were being pushed?
This whole mission was amazing, and the most positive and hopeful thing I have seen as a global event in the last 5 years at least. Bravo and cheers to everyone involved :)
1 hour 29 minutes seems excessive to extract the astronauts; if any of them _did_ have a medical issue they'd be in for a long wait.
The commentary said that the initial problems with the boats approaching Integrity was due to an unexpected swell. Unexpected, in the Pacific?
Edit: all of the Apollo missions, except 8, had their stabilization collars inflated in under 20 minutes. With Integrity today it took nearly an hour more.
I imagine if there was a medical emergency they'd worry less about capsule recovery and safe shutdown. IIRC because the sat phone wasn't working, they had to wait an extra 15 mins to power down the capsule (I guess so they could use its radios?). In an emergency I imagine they'd just leave it as-is
I also like how they waffled on about how winching them up to a helicopter was the fastest option, when they obviously could have shaved an hour off the recovery time by simply having them step out onto the waiting boats!
Having worked for various government agencies for a while I've learned to recognise the signs of the "We're following the procedure whether it makes sense or not, dammit!" attitude you get with large bureaucracies.
I wondered about that. Winching someone who can barely walk and is wearing a spacesuit into a helicopter over choppy water is safer and quicker than parking them on a motor boat and sailing back to the mothership?
What was the real reason? Tradition? Lack of imagination? Photo opportunities?
To play devil's advocate against my own argument: The nearest ship was about 5 km away, which is a decently long boat ride. In choppy waters with a small boat that could be less than ideal for someone who may be injured, weak from an extended stay in microgravity, etc. I assume the plan -- written months or years before the landing -- also had to factor in the possibility that the ships wouldn't have been so close. They did mention several times that the landing was unusually accurate, so it is entirely possible that their pre-planned helicopter ride would have made a lot more sense if they were, say, 20+ km away instead. You don't want dozens of people improvising the procedure in the middle of choppy waters with bad comms, so the best thing to do is to just follow the plan, even if it looks a bit absurd on camera.
“Stepping” from one vessel to another in the middle of the ocean is not like getting on your buddy’s sailboat at the marina even if you have your sea legs. Astronauts don’t even have their earth legs when they splash down; when they return from ISS they can’t even walk right away, though Artemis was a shorter duration mission than that.
Watching this, I can only describe it as holy. An incredible reminder of what humanity can do, and the beauty of our curiosity and the universe around us. I grew up learning that my great uncle was in Mission Control for Apollo; missions like this are what inspired me to pursue engineering in the first place.
It’s been amazing - and inspirational - watching the live stream of Mission Control and the capsule over the last ten days. Or at least having it as background audio. I’m going to miss all these folks I’ve grown to know.
Impressive mission but I feel it's not capturing the public attention because it's actually a step back from the mission 50 years ago when they actually landed men on the moon with tech that was orders or magnitude simpler and less powerful.
I've noticed there's a pretty big difference between the people who remember how routine shuttle flights became and the younger crowd at work. I do think Artimis is cool, but I will admit to being a bit jaded about it as a GenX who watched Challenger live in 2nd grade. The GenZ at work seem genuinely delighted. And that's pretty cool.
A diverse and inclusive crew, a publically-funded mission, an emphasis on science and discovery, and government investment in a long-term strategy, not a quick politcal win.
This current administration has made sure these things never happen again, Artemis is very much the swan song of an America that has died. I am not interested in watching our corpse twitch and calling it life.
I think it you ask the average person they're more surprised that people haven't been going to the moon for the past 50 years. In people's minds it's a solved problem and it's been boring for decades now. If supersonic air travel came back it would only interest people because of reduced journey times. But this doesn't even have anything that directly benefits people so they don't care.
If we're going to have a surveillance state, let's use it for superlative control - one dollar in taxes for every superlative you use in personal life; $0.01/viewer for each one you use in any live televised event.
I’ll note, since it is supremely interesting to me, that Starship is able to communicate with the ground during its whole reentry due to its sheer size and ability to connect with Starlink satellites. I assumed loss of signal due to reentry was a given for any spaceship!
Shuttle in its last days had antennas that protruded outside the plasma just enough for telemetry. Apollo and Artemis reentry are also direct entry from Lunar-Earth transfer orbit using ablative heat shields, so the plasma would be hotter and thicker than suborbital Starship shots with Shuttle style ceramic tiles.
I'm pretty sure it did not stick anything through the plasma sheet- that is impossible. You would eithe melt the thing or just shift the plasma sheet a bit. It forms as air is compressed on contact, simple as that.
What IIRC was actually done was that some antennas were placed on the back of the shuttle & its size was big enough that the plasma bubble would not fully envelope it - it would be open up to space. And that antenna on the back would communicate with TDRS satellites through this gap, enabling contact through the whole re-entry.
Starship does basically the same, just with Starlink satellites instead of TDRS.
Would this capsule had been been able to communicate if it was integrated with starlink or is the size more important? I'd imagine if they could have achieved communication via Starlink they would have done it, but just curious.
It's a function of the shape. On a capsule-sized spacecraft, the ionized plasma completely surrounds the craft, so no radio communications can get in or out. For an oblong-shaped spacecraft, like the Space Shuttle or Starship, the descent tends to be angled such that you have a "hole" in the plasma you can get a signal through.
No, the plasma forms a teardrop shape around small craft like Orion, completely cutting off radio comms. Larger craft like starship or the shuttle which have a roughly cylindrical shape (vs Orion’s circular cross section) aren’t fully enclosed by the plasma. The shuttle had a transmitter attached to its tail for later flights, which could send back telemetry during re-entry.
"Sprint accelerated at 100 g, reaching a speed of Mach 10 (12,000 km/h; 7,600 mph) in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,400 °C), requiring an ablative shield to dissipate the heat. The high temperature caused a plasma to form around the missile, requiring extremely powerful radio signals to reach it for guidance. The missile glowed bright white as it flew."
Awesome, thank you! I wonder if some kind of very long-tethered deployed antenna could enable this for the capsule or if the ratio of long-enough-to-work vs thick-enough-to-not-burn-off-completely just doesn't work. Time to read about the shuttle.
Also Orion and other capsules fall like a rock (steep reentry profile ) compared to shuttle/starship, which intentionally slow down the reentry and kinda glide (ballpark 10min with capsules compared to 30min with shuttle/starship).
tl;dr: capsules get fully enveloped in plasma due to their shape, size and reentry profile
The space shuttle, too, was able to communicate. I imagine the smaller the craft the smaller the angle you can "speak" out of and, below a certain size, it just doesn't work.
I was wondering about that, so I looked up the heat shield issues. It seems like their solution was very defensible and there was every reason to believe it would work out just fine. The plan that did not work as they wanted had a new idea, a double re-entry, and when the results were concerning they backed off to using a traditional single re-entry. That seems like a legitimate fix?
Scott Manley went into the details in a recent video.
The reason the heat shield failed was due to gas buildup inside the ablative material.
This was due to the skip reentry profile they used, where the craft does a single skip (as in skipping stones) during reentry. The high bounce caused the shield to be heated enough that the heat penetrated the material causing gas release but not enough that the material ablated. Thus gas would build up deep inside up until it caused large chunks to break off. They could reproduce this in tests.
The fix was two-fold. First they lowered the bounce height, so a much less pronounced skip, avoiding the lowered heating of the shield. And they tweaked the material formula a bit so it was more porous, allowing subsurface gas to escape rather than build up.
In my understanding of the Manley video, the materials change will only occur for Artemis 3, for which it will be irrelevant as that will not be leaving LEO.
Can somebody help me understand why this does a water landing, like the old Apollo missions, instead of like the space shuttle that lands like a plane?
A big part of the reason is that Orion (and Apollo) reentry speeds are way higher due to the orbital mechanics involved in going to the moon and back. Today's was actually the fastest manned reentry ever attempted.
For reference the shuttle generally reentered at ~17.5K mph, and today's was 24K-25K mph.
It's not clear that we could build a craft with wings that could survive that. So then you're looking at adding fuel just to slow down, plus fuel for the weight of the wings themselves, plus fuel to carry all this extra fuel to the right place, etc.
The space shuttle landed like something resembling a plane, but it is more accurate to say it landed like a concrete brick traveling faster than the speed of sound.
Splashdown-style landings are the simplest and safest, parachutes are always good but adding water makes for another layer of safety (and of risk, to be fair, it could sink).
Wings and rudders and landing gear are very heavy. Then there's the flight control system in all its complexity, along with redundant hydraulic systems and so on.
Lot of the world is ocean & they basically decided the landing point the moment they entered the free return trajectory, 9 days prior - easier to shift the landing point a little to a different place in the ocean place with better weather tha. to switch to a backup airport.
With lunar landing flights they would still have to choose 4 days before, as long as they do direct return.
Eventually you want to break to Earth orbit (propulsively or aerodynamically) and board a dedidacted craft for landing. But till then water landing capsules work.
A Space Planes is needed to land at a runway like a plane.
Space Planes are not only much more dangerous, but are not ideal for this type of mission. They carry a lot of extra weight (wings) that would affect how much fuel is needed to launch them to the Moon.
Capsules are safer and more lean in terms of weight.
The Shuttle was not ideal in many ways. It was used so long not because it was the best option, but because Congress wanted it to keep it going for jobs.
So why do they need to use helicopters and a risky airlift to return the astronauts to the main vessel? Why not just use the speedboats to take them back? Seems really odd and I can’t find any reasonable explanation.
Helicopter -> large boat is much easier, and much faster, than small boat -> large boat. And it's not riskier. I know the inherent risk in flight is greater, but it's also much more managed, so the actual risk is less.
>Why not just use the speedboats to take them back?
They actually covered this in the broadcast: Helicopters are faster to get the astronauts to medical, smoother in rough seas, and there's less risk of being swamped by a rogue wave. Plus, since the astronauts might have fatigue/muscle atrophy/whatever, it complicates potential boat transfers.
The public information sheet implies that in poor weather/rough seas they would do crew recovery in the well deck, sort of like how Dragon works. [1]
From the broadcast, they made it sound like a big factor is the 2 hour program requirement to get the crew out of the capsule. Maybe they can't reliably hit that mark with a well deck recovery?
>Buoyancy is an easier equation to solve than lift.
That's a snappy one-liner but it doesn't address the real concerns.
First of all, subsonic lift is well understood and has been for decades. The answer is much more mundane: The Artemis mission profile does not require payload doors that open, no Canadarm, no requirement to service, launch, and/or capture satellites in orbit, and so like good engineers they designed the minimum vehicle that satisfies the requirements.
Also, the Shuttle was actually much more expensive to reuse than originally predicted.
> subsonic lift is well understood and has been for decades
I said easy. Not well understood. I can fly planes. It’s hard, and has limited room for fucking up. (It’s also hyperbole to suggest we understand lift. We don’t.)
Piloting a boat is easier and more forgiving. Hence, splashdown. You don’t need direction. You don’t need lift. Parachute physics is a backbreaker, but it’s symmetrical. Same for splash.
I love this comment. Thank you. For what it’s worth, I’m not a CFI but I did study actual astronautical engineering. Not much good once we’re in an atmosphere, which, granted, is where the boats and planes go. But I’ll stand by my statement that nobody—apart from interplanetary reëntry and drone teams—fundamentally understands lift. (I certainly didn’t when I was solving analytic solutions by hand.)
>Piloting a boat is easier and more forgiving. Hence, splashdown.
At no point were the astronauts piloting a boat. The reasons they splash down into the ocean has nothing to do with buoyancy being easier to solve, and even less to do with the ease of piloting a boat.
>It’s also hyperbole to suggest we understand lift. We don’t.
Maybe you personally do not understand lift, but "we" do in fact understand it. Please educate yourself before continuing this discussion any further.
Aerospace engineer here: The simple answer is that the Shuttle form factor is unnecessarily complex for this mission.
A small Apollo-style capsule that parachutes into the ocean has a simpler mission profile, which allows for simpler technical and operational requirements, which in turn reduces program cost.
Too fast. The space shuttle used to reenter sometimes over us in California. I remember in elementary school the entire building shook, and that was just one building! The amount of energy being dissipated is literally astronomical! If you've never experienced the sonic boom of reentry it is something to marvel at. It literally feels like an earthquake!
Watching that capsule fall out of the sky at high speed from the teaching cameras was nerve wracking! Awesome footage, exciting to watch it live in such detail.
What is coming into view from the top center at 08:26:25 [0], right after the commentator says, "the weather conditions remain go"? It stays visible for more than seven minutes before disappearing behind the horizon.
Not for the same reason as you, the whole time I was thinking "I'm pretty sure NASA can assess the risk of their mission better than an Internet famous blogger", despite the sentiment on HN at the time being very negative after reading these words [1].
These days the only qualification required for people believing anything you say is to have a blog and strong critical opinions about $AUTHORITY. Software engineers somehow believe they are knowledgeable in any topic just because they spend a lot of time reading on the Internet.
I get that there are people who think the moon landing was staged, but are there really people who think rocket launches are staged? Because it's pretty easy to go witness one yourself.
For All Mankind aired an episode today that movingly commemorated the fictional lead character Ed Baldwin's Apollo 10-like in-universe mission on the same day that the real world Artemis II mission which also strongly resembles Apollo 10 landed safely. A strange and moving coincidence.
It's hard to know who was right. All of these things can be true: it made it back ok; it had a high chance of making it back ok; it should've had a much higher chance of making it back ok. Most of the concerned people were stressing this last point, that it should've been safer than it was. They still thought it had a quite high chance of making it back ok. It took a lot of shuttle missions before Columbia failed.
While I agree with your main point (it's hard to know who was right), the people who agreed to proceed were NASA engineers/astronauts who had actual numbers to analyze, while the doubters (even Camarda) only had theories.
We'll need a post mortem to know what the margin of failure was. This said they had made changes since the first flight so we'd expect less to no damage this time.
This almost brought tears to my eyes. I can only imagine how people felt when the first astronauts got to the Moon, and then when they got back to Earth in one piece.
I noticed a delay between video and audio - the announcer on the NASA official live broadcast said splashdown before the the capsule splashed down on video. Was it intentional (in case something happened)?
Also, what were these puffs on thermal camera after the main chutes were deployed?
My suspicion was they were burning excess propellant, rather than attitude adjustment while under the parachutes. Though who knows how much propellant remained. It could be quite a bit more than it appears was used.
Not just excess - excess and toxic. Hydrazine derivatives and nitrogen tetroxide, IIRC. They are hypergolic, too, so the easiest way to vent them is just to run the engines until empty. However, to prevent moving the craft too much, you do short bursts.
There are opposed thrusters, but I assume that in atmosphere and under parachute canopy it’s harder to make sure they are perfectly opposed.
Heating likely plays a role as well.
I am not a rocket engineer, but I have read How Apollo Flew to the Moon and Ignition!: an informal history of liquid rocket propellants, both of which cover these issues. Highly recommended.
The short bursts are just the period of the control cycles. Control cycle starts, loop sees error, commands thrust; next control cycle starts, loop sees error is nulled (or in deadband), commands no thrust.
I was wondering about that too, I assume maybe there was some additional adjustments needed to land in the right spot, but they didn't mention it on the stream.
All those countries are essentially American vassals. No shade to them, just stating the reality, and not really sure why we need to keep pretending. There's no shame in that. It's often the smartest move to join forces with the big guy in the block!
How? I struggle with this. It all seems like a fearful waste of money and resources. We can't live on the moon. We can't live on Mars. It is a fantasy. We have so many problems here on Earth that are more important to solve than sending a handful of men to the moon (again).
As I've said before. This is a huge achievement. And also is the most effective political propaganda ever. Bravo to everyone involved .
This is not sarcastic. This is very much meant. I love that America does this. We still get to evoke an awe which previous empires awesome as they may be, could never match. American superlatives are amazing. God bless America
I don't know how to describe the feeling but it feels like a bad movie remake. Maybe I am just a sucker for practical effects and not 2020s CGI to stick with the metaphor and conspiracy...
In 2028, so only 2 years from now. They will be able to bring 4K pictures and videos of the walk on the moon and they promised not to delete them this time.
They will have Nikon cameras, GoPros, and iPhones with them.
Very different from the videos taken with the Gameboy Camera.
As a long time space nerd, I'm not sure what this accomplishes by repeating the previous stunts that failed to usher in the promised space frontier.
Apollo was, IMO, not successful at changing the course of human history. A really cool footnote, sure, but everything else that was to follow, nope, just a bunch of neat, interesting but ultimately meh science missions.
An exciting change would be more like Delta-V/Critical Mass, but NASA is not going to deliver that, at least not in any form it has taken thus far.
The guidelines ask us to avoid being curmudgeonly. I'm sure you didn't mean to come across that way, but could you try not to make Hacker News the kind of place that responds with “meh” to a successful space mission?
My pessimism comes from a hindsight that the Apollo missions, while amazing failed to create the future they promised. Looking at how the missions were designed, the political focus, the academic infighting of NASA scientists trying to keep niche research funded.
I fail to see how this time, the same strategy will produce a different result.
I also don't expect benevolent billionaires to fill that either. I hope I would in their place, but I'll not likely get the chance.to find out.
To end on an optimistic note, tang and Velcro are pretty dope.
I blame the "space race" narrative - it made everything unsustainably expensive just to beat the goal of landing on the Moon by the end of the decade and before the Soviets. That also made the program even more dependant on political whims and easy target for budget cuts in the Vietnam era.
I recommend looking into the space flight plans from the pre Apollo - while tere were bonkers ideas like Project Horizon, most of the plans sounded quite sensible, with incremental building of space infrastructure and emphasis on cost and reusability (in the 1960s).
Of course when it became a race all the sustainability and infrastructure went out of the window and got sacrificed in the name of speed. :P
My point is this path doesn't lead to the future, it leads to the sad state of space between Apollo and this Shark Jump.
The first Orion (nuclear pulse) has a much more interesting story and would have made us an interplanetary species before we had the iPhone. But it was killed by Kennedy, became space wasn't what he was worried about.... And maybe hundreds of nukes in space might make some countries edgy.
More than that, people today seem to be saturated with sarcasm.
It's especially tragic with younger people who seem to have no experience with handling genuine sincerity. They laugh nervously at it, as if they're unfamiliar with how to handle someone saying what they actually think and feel.
The questions from the news agencies and their responses are not scripted. I encourage you to listen to the Q&As the astronauts and ground crew had during the mission and judge their character on that. You won't find any public figure / politician with any amount of media training that even comes close to their level of genuine humanism, humility, and professionalism.
Why this was such a big deal? Haven't people reach the moon so many years ago? By this time we should have lunar bases, not cheer so much that we got past the moon at a few thousands miles away.
Glad that they're safe and sound.
It's worth pointing out that this is the first extremely public, widely acknowledged high risk mission NASA has done in over 50 years. The Shuttle was risky, but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
According to NASA's OIG, Artemis acceptable crew mortality rate is 1 in 30. Roughly 3x riskier than the shuttle. There genuinely is a world where they don't make it back home.
I am grateful that they did. And I'm grateful that we're going to go even further. I can't wait to see what Jared's cooking up (for those who don't know, he made his own version of the Gemini program in Polaris and funded it out of pocket).
> Artemis acceptable crew mortality rate is 1 in 30.
This seems insane to me. That X decades later we accept, with all our advancements in tech, a weaker system than ever before. That if we send 30 people we _accept_ that one is possible to die.
That's the starting point? That's what we document as acceptable?
Yes, and the memories of Apollo are made rosy by hagiography. I even wrote an entire thing to explain why, https://1517.substack.com/p/1-in-30-artemis-greatness-and-ri... (yeah, shameless plug, sorry - it's more for the citations than not. You can read the standards and reports I've linked to)
But if I'm allowed to repeat myself from elsewhere in the thread and the meat of the above thing,
It's physically not possible at our current level of technology to make this "safer" due to the distances and energies involved. Even with the Commercial Cargo and Crew Program (C3P), NASA has set the acceptable mortality threshold at 1 in 270 over the entire mission and 1 in 1000 on ascent / descent. If they could set it higher by gaming the math, they would. They can't.
We're a very primitive species, and the forces involved here are genuinely new. And no, Apollo wasn't much better either, at least 10 astronauts were killed in training or burned alive, as well as (far worse, because astronauts sign up for the risk) one member of ground staff.
People love to hate the Shuttle, and it ended up being subpar / fail expectations due to the political constraints NASA was under, but the Shuttle was a genuine advance for its time – a nonsensical, economically insane advance, but still an advance. If you look at the Shuttle alternative proposals / initial proposals as well as stuff like Dynasoar and Star Raker, you'll see NASA iterating through Starship style ideas. But those were rejected due to higher up front capital investment at the time.
The Shuttle is an odd franken-turduckling, because it was designed for one mission and one mission only. And that mission never happened. That cargo bay existed to capture certain Soviet assets and deploy + task certain American space assets and then bring them back to Earth.
And that's the bit that's hard to emphasize. The fact that the Shuttle could put a satellite up there, watch it fail, then go back up, grab it, bring it back, repair it, then launch again was an insane capability.
Was the program a giant fuck up at the end? Yes. But does that mean Artemis will be safer than the Shuttle? No. That's not how the energetics, time from civilization, acceptable risk profiles etc. work out.
That was a great article.
Adding to it - Apollo 13 was a mission where 3 men should have died, but somehow didn't. If it had happened while the LM was on the moon, you would have had the CSM lose power, and then two men on the moon would have had no way to return home.
(And for the shuttle design mission - my understanding is it was likely the ability to do a HEXAGON-style film return mission in a single orbit, before the Soviets knew what was happeneing.)
Thanks!
note - I can't verify any of the following, it's more - for lack of a better term - aerospace nerd fan theory at this point.
Post-collapse, people think that the Buran justification was paranoia. But based on what I've read / seen (though this is getting hard to source, so I might be just good ol' hallucinating here), they weren't entirely wrong. The subtext around that large payload bay had to do with the Soviet pursuit of systems like Fractional Orbital Bombardment System (FOBS) https://en.wikipedia.org/wiki/Fractional_Orbital_Bombardment... that weaponized space.
Again, there's a reason for those ASAT tests. There's a reason for the weird specifications set in the early 1970s for the Shuttle. And I don't think deploying a spy satellite alone is it. But this is speculation. AFAICT, nothing was put on paper.
It would have been an incendiary WW3 starting act to capture a Soviet asset. But I think it is understandable if certain people within the American blob wanted that capability at hand.
I wish I was immortal. I'd drop everything for a decade and try to find people from the time who're still alive (and some still are!) and ask them these questions directly - on the record – for posterity's sake. I suspect, we came much closer to war via space than most people think. And because we didn't, we'll eventually repeat these mistakes.
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Oh and then there was the documented attempt to capture Salyut-7 https://www.thespacereview.com/article/2554/1
Somehow all the numbers just happened to line right up. :)
>documented attempt to capture Salyut-7 https://www.thespacereview.com/article/2554/1
This isn’t true. The same article even explains that.
From that article: “It takes only some basic fact checking to debunk all the preposterous allegations…”
Yes, you're right. I'm not going to pretend that this is a serious proposition. There isn't a lot of evidence to support it.
For me, it's a fun conspiracy theory to engage with. I'm only doing this for the love of the game as it were. Please don't take it that seriously.
But you have to admit, it is a fun theory. A lot of the claims made by the Russians / Roscosmos are most likely false, but if you notice the article says,
Whether or not said documentation can be trusted, which bits could be taken as true v. what's just insane paranoia is something that would require more work to discount than most would think. Because, as I've said, the numbers do line up from the article, The Shuttle was an amazing piece of technology with amazing capabilities. See: https://en.wikipedia.org/wiki/STS-41-C and https://en.wikipedia.org/wiki/STS-49and this is one of my favorite missions, https://en.wikipedia.org/wiki/STS-51-A (with my favorite space selfie)
Fun fact, the original deorbit plan for the Hubble was for the Shuttle to bring it back and then put it inside the Smithsonian, https://www.hou.usra.edu/meetings/orbitaldebris2019/orbital2...
(the Smithsonian part is IRL lore, and isn't mentioned online, AFAICT)
The only people who took seriously the idea of a Shuttle FOBS were the Soviets, and frankly not even all of them; as far as I've ever seen credible evidence to substantiate, it never went much past a single position paper from the early 80s. The idea that Buran was meant as a MAD-restoring FOBS has, so far as I know, not even that much support. (If you know of primary sources, in translation or otherwise, please link them.)
Read Payne Harrison's 1989 novel Storming Intrepid, followed by NASA publication SP-4221, "The Space Shuttle Decision," from 1999. [1] The first is a pretty good depiction of what you're imagining, and the second explains why the imagination of a technothriller author is where that idea went to die. Then maybe give your head a shake. If Reagan had violated the Outer Space Treaty - via NASA of all agencies! - how do you imagine it'd have stayed secret over these forty years just past?
[1] https://web.archive.org/web/20241229052235/https://ntrs.nasa...
> If Reagan had violated the Outer Space Treaty - via NASA of all agencies! - how do you imagine it'd have stayed secret over these forty years just past?
While I have no reason to believe this particular escapade, I do expect that there are a thousand such wild stories that have remained secret. Watergate seems obvious and explosive to moderns, but at the time it could easily have gone undiscovered or unremarked. How many other similar scale plots, domestic and international, succeeded or failed without ever being surfaced into the history books? A few? Dozens? Hundreds? ¯\_(ツ)_/¯
Nice article, although I'm not so sure about this part:
> There’s a reason why there wasn’t an Apollo 18, or 19 and 20. Even though funding had been secured, an executive decision was made to kill the program early, because LoC was inevitable.
Was funding really secure? I believe that was the main sticking point; a quick search [0] seems to confirm this, and the John Young quote below backs it up: "Even if they’d had the money..." Not to say the risk wasn't a factor too of course, but it doesn't look like funding was otherwise guaranteed.
Anyway, I think what sets the risk of the Shuttle apart from Apollo is summed up nicely in one of the quotes (in reference to the Apollo program): "The awareness of risk led to intense focus on reducing risk." In the Apollo program, there was a pattern of rigorously hunting down and eliminating any possible known risks, leaving unknowns as the primary source of risk; on the other hand, the Shuttle program let known risks accumulate continuously until crews paid the price for a bad draw.
When debris hit Atlantis on STS-27 [1] and the shuttle only survived on a one in a million stroke of luck -- the completely broken tile happened to be over an aluminum mounting plate -- it should have been taken as a free lesson on one more known source of risk to eliminate. Instead, it led to seven people dying completely preventable and unnecessary deaths a few years later.
Spaceflight is inherently risky, it's true. That's why things like the Orion heat shield are so worrisome; because it is physically possible at our current level of technology to make it safer, and yet for political / funding / etc. reasons we're not doing the best we can.
[0] https://airandspace.si.edu/stories/editorial/why-did-we-stop...
[1] https://en.wikipedia.org/wiki/STS-27
The Saturn V's existed. Saturn V serial numbers were designated as S-5## where # is an increment from 1. https://en.wikipedia.org/wiki/Saturn_V#Launch_history <--- see the Saturn V numbering scheme here.
SA-513 was repurposed from Apollo 18 to Skylab. SA-514 was meant for Apollo 19. They put it on display. SA-515 was also chopped up and put on display. Some parts were used in Skylab. https://www.space.com/nasa-extra-apollo-moon-saturn-v-rocket...
So there were 3 Saturn V already assembled and in existence.
Did the CSMs and LEMs exist? CSMs had a similar serial number scheme. And they designated "Block 1" and "Block 2" (iterations of the spacecraft design based on testing) CSM-0## and CSM-1##
The CSM used in Apollo 17 was CSM-114. On wikipedia it says that CSM-115 and CSM-115a were never fully assembled and cancelled, but if you look past that, you can also see that Skylab used, CSM-116, CSM-117 and CSM-118. These were Apollo CSMs, fresh off the same assembly line. https://en.wikipedia.org/wiki/Apollo_command_and_service_mod...
So there were 3 CSMs.
What about LEM? Similar number scheme, LM-## which is incremented with each one made. So first one was LM-1 and the last one used on Apollo 17 was LM-12. LM-13 is on display in a museum. LM-14 was on the production line (along with LM-15??) and a "stop work" order was issued and they were scrapped. Yes, they were literally broken down and turned into scrap. https://www.businessinsider.com/nasa-lunar-modules-lm14-lm15...
So NASA had 1 LEM and 2 were on the way. I think, we can charitably say that there were 3 LEMs available at the time. I think it's fair to say that...
There were 3 LEMs.
Did they have 3 crews? Funnily enough, they did have 3 crews already assigned! What a coincidence. https://web.archive.org/web/20181224161154/https://nssdc.gsf... :)
So the Saturn Vs existed and had been paid for. The CSMs existed and had been paid for. The LMs existed / were on the line and had been paid for. The crews existed (and had been partially paid for).
So what is the "funding shortfall" that caused America to stop going to the moon?
The "funding shortfall" here is the money required to pay for the ground crews and personnel for carrying out the mission. And that amount was $42.1 million out of $956 million for Apollo. The total NASA budget was, $3.27 billion that year.
$42.1 million. NASA admin just couldn't find $42.1 million of ground staff salaries etc out of the remaining $2.3 Billion budget.It's probably a coincidence that this happened right after Apollo 13. The decision was announced on September 2nd, 1970. Apollo 13 happened in April, 1970.
----
So yes, the funding was there. I suspect the "funding cut" argument was an attempt to save face; after the US Government (and I mean the Government, it's clear both the White House and Congress were involved) decided to cut the cord post-Apollo 13.
I also suspect this is one of the many "open secrets" lost to time. It might have been known by "everyone" in the know at the time, but those who knew died off, and history crystallized around the written page.
> one more known source of risk to eliminate.
How could they have eliminated that risk?
We can look at what NASA did after the Columbia disaster; namely, redesign the external tank, employ stricter quality control of the foam across the board, better monitoring of the heat shield integrity, and adding contingencies for being stuck in space with a damaged shuttle.
- They replaced the specific foam insulation that struck Columbia with external heaters, and redesigned other areas where foam was necessary to ensure greater structural stability + minimize damage to the shuttle in case of breakage. They also began more thorough inspection of any heat shield panels that would be reused between missions
- They added various cameras, both on the shuttle and on the ground, to monitor the heat shield throughout launch, plus accelerometers and temperature sensors. Also, the heat shield was checked manually on every mission once in orbit for damage, both with an extension to the Canadarm, and with ISS cameras when possible (a funky maneuver [0] where they would do a backflip to flash the shuttle's belly at the ISS for it to take high res pictures)
- Every mission from then on had a backup plan in case the shuttle wasn't in a state to return to Earth (this wasn't really the case before then, which is kinda wild). Another shuttle was always ready to launch, with a new configuration of seats to allow for sufficient crew space
- They sent up equipment and materials for repairs in space with every launch, though admittedly the usefulness of that was dubious and the repair kits were never used
Perhaps 'eliminate' was too strong a word, but there's no reason these precautions couldn't or shouldn't have been taken before it resulted in deaths and the loss of a spacecraft. (well, other than the aforementioned funding/politics/organizational failure)
[0] https://en.wikipedia.org/wiki/Rendezvous_pitch_maneuver
>Every mission from then on had a backup plan in case the shuttle wasn't in a state to return to Earth (this wasn't really the case before then, which is kinda wild). Another shuttle was always ready to launch, with a new configuration of seats to allow for sufficient crew space
Actually the backup plan almost every time was to just stay on the ISS until another Shuttle could be prepared. They only had another Shuttle on standby a couple times, during missions where they weren’t going to the ISS.
>They sent up equipment and materials for repairs in space with every launch, though admittedly the usefulness of that was dubious and the repair kits were never used
Yeah it wasn’t even useful for a situation like Columbia. It didn’t lose a few tiles or something, it had a giant hole punched into its wing.
There’s no fixing that in space. So I personally think they focused on situations they could theoretically fix, even though those situations weren’t what happened to Columbia.
Worth mentioning, this is all particularly fresh in my mind because of a recently released video by the excellent Classic Aerospace History channel on YT, "A Brief History of the Space Shuttle". It's two hours long and provides a reasonably detailed overview of the program, would recommend if you're into that sort of thing: https://www.youtube.com/watch?v=WtmOVxcga-Y
The risk couldn't have been entirely eliminated, but most likely the external tank insulation could have been modified to at least reduce the risk of chunks breaking loose and damaging the thermal tiles during launch.
Im not really convinced SLS and Artemis are best effort projects; we improve through refinement, and the only way to get there is cadence. More launches with the same general mission requirements.
One launch a year is not even close to what we can manage with our current technology, to the point where the scope is too small to be legitimately worth doing.
Its not solely a matter of energy; its about opportunity for learning. The current scale is too small to be worth doing at all.
If it was a program of something like >50 payloads over a decade, that gives enough opportunity for refinement, in cost, safety, and scale manufacture methods to actually see something new.
The value of a mission like this isn't only in the narrow technical data it returns. Its value is also institutional. Once you have an actual crewed mission orbiting the Moon, the program becomes concrete rather than aspirational. That creates momentum inside NASA and among contractors, strengthens the credibility of follow-on lunar missions, and accelerates work on the many parallel systems a sustained lunar program actually requires.
I agree entirely that it's much easier to imagine a successful moon program built around repeatable missions at high cadence, so I'm not disagreeing on that point. I would just push back on the idea that this has little or no value.
If I may be allowed one nitpick. Without fully understanding the FAA doc you link to in the article, I think it would be better to say something like loss of a plane is a 1 in a billion event for commercial airplanes. Many types of parts used in airplanes and jet engines break at much higher rates though, they just don't necessarily cause a plane loss when they do.
Wouldn’t the soviets or any other adversary prepare against letting NASA capture their satellites? You need a very small amount of C4 in the satellite to destroy the shuttle in the event of capture. Tampering with other entity‘s satellites can best be done with satellites. That also frees resources needed for bringing life support systems to orbit.
But at that point if you're building in a self-destruct for a weapon that can be so dangerous it's worth sending a shuttle to take it away from you, surely it's better to adversarially trigger the self-destruct and not bother sending the shuttle. So the C4 option might simply be a bad idea: make it more difficult and costly to remove your weapon, rather than triggering your own self-destruct.
There are easier cheaper ways of destroying a satellite than sending a space shuttle. We would have only sent a space shuttle to capture it for intelligence purposes.
Artemis certainly seems safer at least in launch. It has an escape system that could be triggered throughout launch. In comparison shuttle could not abort at all until srb separation and after that could have needed risk aerodynamic manoeuvres.
Thanks for sharing your article - very well written.
I am stunned to see that LoC risk assessment.
I kept wondering to myself over the past week, “will this be the last USA-supported human space travel if these astronauts don’t survive?”
I’d have a hard time imagining the general public would support any future missions if they hadn’t survived.
These astronauts are some elite humans. My respect for them is even greater now that I’ve seen the risk quantified.
The Smithsonian article on John Young that you linked to is a good one. The only John Young quote they didn't include that I wish they had was his response to the proposal to make STS-1 an on purpose RTLS abort: "Let's not practice Russian roulette."
> It's physically not possible at our current level of technology to make this "safer" due to the distances and energies involved.
That's not true at all.
It is entirely within current technical and fiscal means to launch a much more robust and powerful craft that is capable of goign to the moon and returning with lower velocity by sending it up in pieces with Falcon 9 (Heavy) and assembling it in LEO before launching to the moon.
This mission architecture is intrinsically compromised by social constraints in the form of pork barrel spending dsfunctional decision making process.
Given current levels of technology, this would require docking with a series of space tugs. Not impossible, but Blue Origin is the only organisation working on this at a meaningful scale.
There was also Nautilus-X which never made it beyond the concept stage.
Well said.
> We're a very primitive species, and the forces involved here are genuinely new.
It's absolutely wild to me that we went from inventing flying machines to putting people on the freaking moon in the span of a human lifetime. What we've accomplished with technology in the last 500 years, let alone in the last century, is nothing short of remarkable.
But, yes, in the grand scheme of things, we're still highly primitive. What's holding us back isn't our ingenuity, but our primitive instincts and propensity towards tribalism and violence. In many ways, we're not ready for the technology we invent, which should really concern us all. At the very least our leaders should have the insight to understand this, and guide humanity on a more conservative and safe path of interacting with technology. And yet we're not collectively smart enough to put those people in charge. Bonkers.
>It's physically not possible at our current level of technology to make this "safer"
Absolutely it is, if NASA was not constrained by congress to use shuttle components to build the spacecraft, they could have had double the payload mass capability at least (the Saturn V was almost twice as capable, we should be able to do a little better now). This would provide tons of extra margin for safety, and allow a shorter and thus safer route to the moon as well.
Shuttle was awesome and the people who love to hate it can personally fight me.
NASA certainly took many risks back then. People remember Apollo 11 for the landing, but for example on Apollo 8, with a fire roughly 2 years earlier that killed 3 astronauts, they had one manned mission (Apollo 7) and then immediately sent Apollo 8 around the moon with ONE rocket nozzle that had to work (and no LM to escape into, as the Apollo 13 astronauts had to do), basing their faith in trajectory mechanics which hadn't been tested that far out
The ejection seats on Gemini were a joke, and there's an anecdote Gene Kranz tells in his book about Gemini 9 where he thought it was too risky for them to cut away the shroud on the thing they were going to dock with (the Agena having blown up on launch) but NASA was this close to overriding him and doing it anyway (they were saved by the astronauts vetoing it, which was good because the EVA, separately, that Gene Cernan did was incredibly harrowing. he was sweating, way overworked, could barely see)
I often think about the shuttle program in relation to all these crazy complicated, wildly expensive, and incredibly fragile space telescopes we're sending to LEO or the Earth-Sun L2. Would be damn useful to be able to repair/upgrade these things like with Hubble.
Obviously I realise the shuttle program was pretty far away from being able to head out to the Earth-Sun L2(AB, and wasn't even working towards it. But man, it would be nice to have that ability.
Really? Seems like it would be cheaper to build extra telescopes (economy of scale). When one of them breaks, just launch another.
"As of 1 April 2026, there have been five incidents in which a spacecraft in flight suffered crew fatalities, killing a total of 15 astronauts and 4 cosmonauts.[2][how?] Of these, two had reached the internationally recognized edge of space (100 km or 62mi above sea level) when or before the incident occurred, one had reached the U.S. definition of space at 266,000 ft, and one was planned to do so. In each of these accidents, the entire crew was killed. As of April 2026, a total of 791 people have flown into space and 19 of them have died in related incidents. This sets the current statistical fatality rate at 2.4 percent."
[wiki link](https://en.wikipedia.org/wiki/List_of_spaceflight-related_ac...).-,During%20spaceflight,fatality%20rate%20at%202.4%20percent.)
2.4% is not bad given how new this still is and how extreme the speeds and energies are.
Note that all the fatalities have been launch or landing related, not in space itself. Clawing out of this gravity well is tough. Make Earth a bit larger and you’d never get off it without something like NERVA or nuclear pulse Orion.
I wonder sometimes if that’s another thing to toss in the Fermi paradox bucket. Many rocky planets might be much more massive than Earth. On one with 3X our gravity a space program might never get going.
NERVA as envisioned had terrible thrust to weight ratio, not really usable to launch from a Super Earth. Nuclear lightbulb, orion or heck NSWR would likely work though. And bonus points for not having to think about landing systems for the return trip. ;-)
In that case aliens from a super Earth would be unable to get off it unless they decided to salt their biosphere with fissile waste. NERVA is at least contained if it works properly.
So no space program from a super Earth until they figure out not just fusion but compact high density fusion that could fly. You’d need stuff like in The Expanse, or at least in that rough ballpark.
Using fission is something they probably wouldn’t do unless they faced an existential reason forcing them to go to space, like deflecting an asteroid.
The lack of plate tectonics is a much bigger obstacle on Super-Earths, then g.
Yeah the more I learn the more I buy the rare Earth explanation.
Life may not be that unusual but it might be mostly just goo: little extremophile type bacteria and maybe very tiny creepy crawlies living in deep seas, underground, in liquid mantles in ice moons, etc.
But to get stuff even as sophisticated as frogs and bunnies, let alone something that can try space flight, requires a place that is all of: big, stable, with abundant energy, with high enough metallicity, and in an environment well shielded from flares and impacts.
There may not be a lot of places like this.
I suspect that it is NOT a weaker system than before, it is more accurate about the mortality rate. In other words, there are fewer "unknown unknowns" than there were in the 60s and 80s, partially because of explosions that took out previous astronauts.
(Some would snidely say as long as they don't put seven people on the rocket they'll be fine.)
1 out of the 12 crewed Apollo missions resulted in the death of the crew, so a 1 in 12 effective mortality rate.
Apollo 13 was a very close call. If that had ended in failure the mortality rate would have been 1 in 6.
So 1 in 30 would be a pretty clear improvement from Apollo, and we are a lot better and more thorough at modeling those risks and testing systems than we were during the Apollo program.
Is 12 enough of a sample size to make a statistical judgement? What if there were 20 more which didn’t have a loss of life? Is it then 1/30? What if there were 20 more?
The risk factor is calculated _per mission_ from what I understand. You can have three accidents in a row and nothing for decades but the risk itself can still be 1 in 30.
Your point is fair and and important distinction. I think when estimating a risk factor though, this empirical data, while a low sample size, is a valuable statistic because it's empirical, and not that small of a sample size. Maybe going forward, we have 3 risk levels:
So the risk factor for Apollo could have actually been 1/1000 but they were just really unlucky?
If I toss a coin four times and it comes up heads three and tails once, it doesn’t mean that there’s a 75% chance that this coin lands heads up. Be careful about conflating risk factor and mortality rate.
Space is hard. If we didn’t accept these parameters we wouldn’t go to space. Apollo lost one entire crew and almost two, the Space Shuttle lost two missions where the whole crew died. The risks are real.
Turns out riding on top of controlled explosions is a risky engagement.
It honestly says something about how absurdly risk averse our society has become that an 1/30 chance of death is considered too high for a literal moonshot. You can advertise a 1/3 rate of slowly choking in vacuum and I bet you will still get a five mile long queue of people signing up for the mission.
If you want a historical comparison, over 200 men left with Magellan on his voyage around the globe and only 40 returned.
Agreed, but people were often forced into those conditions. Or were forced to make an impossible survival decision.
Were Magellan’s men volunteers? For example, in the incident with The Wager, 1,980 men left on 6 ships, and only 188 survived. Men of the original men were press-ganged (kidnapped to crew these ships), and a lot of them were even taken from an infirmary and not in great health. And, of course, conditions were pretty terrible.
So yeah, we’re more risk adverse… and also a lot better at keeping people alive. I think most people would not have signed up for some of these really risky endeavors if they knew the true risk.
https://en.wikipedia.org/wiki/Wager_Mutiny
https://en.wikipedia.org/wiki/Shanghaiing
Maybe we should be glad that afawct none of the people exposed to the risks of artemis ii mission were force on it against their will. I'd bet the even in The Wager you would have have some clear headed people who knew the risk and still chose it
Or the extreme casualty rates experienced by the (mostly very young) East India Company clerks in Calcutta. From Dalrymple's The Anarchy:
"Death, from disease or excess, was a commonplace, and two-thirds of the Company servants who came out never made it back – fewer still in the Company’s army, where 25 per cent of European soldiers died each year."
You're acting like if it fails they can just say "Well we said it was 1/3!" and then just get on with it. "Oops we lost a zillion taxpayer dollars and no one will mind and maybe they'll give us more money this time around!" That's just not how the world works.
Crazy indeed, glad that someone else has already mentioned Magellan, because that’s whom I also had in mind. Not sure there’s a solution for this because at this point the risk scare has been institutionalized among most if Western (and not only) society.
Crossing the Atlantic and the discovery of the Americas? How many deaths were acceptable during that initial period of exploration? That’s where we still are with space.
And the atmospheric entry is still the same as 1969. Physics doesn’t change.
Actual death rate for astronauts so far is 19/791, or 1 in 40.
You are comparing orbiting earth in a shuttle to a lunar flyby in a pod. Very different risk profiles.
First couple of crews to orbit the earth at 0’ AGL had mortality rate of 9 in 10.
I’d say we’re doing better!
> That X decades later we accept, with all our advancements in tech, a weaker system than ever before
how do you keep past performance while stop performing it for XY decades?
A lot of advancement is multipurpose. CNCs are more accurate than machinists, computers are faster. And we have a lot of the technical knowledge written down.
Machinist never stopped working even after advanced CNCs proliferated. Humans had records of how things were made and yet new generations had to relearn it - and fail in the process.
This mission is not about sending stuff out to deep space. Its about sending out new generation of humans to deep space.
Even if you could guarantee that these new humans have exact same experience of past humans, can we guarantee that past decades simulations or theoretical knowledge acquired - while NOT actually doing something - will effectively reduce the chances of mortality?
We stopped going to the moon because it's a vanity project. It's expensive, risky, and there isn't much more science to do or that can't be done by robots.
Hopefully this time we can keep going for what we can do for engineering instead of what we can do for science.
If we got to a point where going to the Moon was significantly safer than that, we’d better start trying things even more ambitious and risky or we’ll stagnate as a species. The fatality rates for circumnavigating the globe or settling in North America or attempting to invent a working flying machine were much, much higher than that.
This was the farthest humans ever travelled from earth, even farther than apollo 13. Intuitively the farther you go the higher the risks are
Landing on the moon is enormously riskier than simply going further out.
I'm answering the claim about Artemis being more dangerous than the space shuttle. Obviously landing on the moon is a lot riskier.
They could go twice the same distance, the risk would be roughly the same at that point. It's mostly the complexity and changes that make it more risky once the initial trajectory is in place.
You need a lot more impulse and more fuel to go twice as far. Probably more correction burns. A longer final burn before entering the atmosphere. So the risk of loosing the engine is much higher and probably increasing more than linear with burn time/change of impulse.
You cannot really determine what the risks are before trying something new.
overall construction in the US had a measured death rate of 1 in 1000 people in 2023. i think we can accept far higher rate for space travel.
That was the fair estimate for the Shuttle program. NASA caught hell in public, justifiably, for pretending otherwise. But astronaut memoirs such as Mullane's excellent Riding Rockets paint a much more nuanced picture.
I waited until splashdown to permit my emotions to get involved, and I'm glad I did. It was really something earlier, to hear my whole neighborhood bar set up a cheer for an American mission to the Moon.
Come on! No one is forced to get on the rocket. If you don’t think it’s worth it, don’t go!
From a social perspective, I would recommend to think of the average death per capita of an effort, which is effectively nil for Artemis (very few astronauts vs us population) compared to generating electricity with coal, which kills many annually.
The shuttle didn’t accomplish that much and didn’t get us as far as Artemis just did, the risks are well worth it. Nobody is forcing the astronauts to do their astronaut thing, imo they’re aware of the risks they’re taking, and kudos to them for that.
Wai how is it weaker, like genuinely?
Eh yeah? This is frontier, pioneer stuff. We should have a greater appetite for risk as long as it’s completely transparent and the astronauts know what they’re getting into. Realistically though, there is essentially a rocket a day going up and they rarely fail anymore, so the true risk is probably much lower than 1 in 30.
Insane to you? why don't you tell us what you have contributed to the world to improve this outcome even if by .01%
There are over 8 billion people on earth.
Astronauts are, as a group, extremely risk loving. Every single person who signs up to go into space knows what they’re signing up for - they’ve spent their entire life working for the opportunity to be put in a tin can and shot into orbit atop a million pounds of explosives. There’s a very valid critique that NASA has become far too risk averse - we owe it to the astronauts to give them the best possible chance to complete the mission and make it back safely, but every single person who signs up for a space mission wants to take that risk, and we don’t do anyone any favors by pretending that space can be safe, that accidents are avoidable, or that the astronauts themselves don’t know what they’re signing up for. A mission that fails should not be considered a failure unless it fails because we didn’t try hard enough.
My father, who flew combat missions for the Navy in Vietnam and then became a test pilot, told me after the loss of Columbia that if he had had a chance to make that flight and spend 7 days in Earth orbit, even knowing that he'd burn up on reentry, he'd have done it.
One way to see it:
(and potentially) So you have a possibility of a guaranteed exciting life for a death that you anyway will have, but doing something you love, it's not too bad.Your father is a better man than I am.
Highly recommend The Right Stuff by Tom Wolfe about the Gemini astronauts. They mostly were test pilots prior.
The movie was good too. I haven't seen it in years, but from memory:
Gordo! Who's the best pilot you ever saw? -- You're lookin' at him!
Loan me a stick of Beemans.
Light this candle!
It just blew!
No bucks, no Buck Rogers.
> Artemis acceptable crew mortality rate is 1 in 30. Roughly 3x riskier than the shuttle
Do you have a link? I’m asking because it is very easy to make mistakes when comparing risks. For example https://news.ycombinator.com/item?id=47725961 translates that into “That if we send 30 people we _accept_ that one is possible to die.” If that interpretation is correct, given Artemis has a crew of four, that looks more like a 1:120 chance of a mortality of 4. I think that would make it an improvement over the space shuttle.
For context, Jared is NASA Administrator Jared Isaacman. I didn't know, so I think it could be useful for others.
> Artemis acceptable crew mortality rate is 1 in 30.
How did they arrive at that number?
(Eg. Did they arbitrily establish the target at the outset? Or did it evolve by gauging the projected failure rate of their core mechanical etc. systems as those began to take shape, then establishing a universal minimum in line with that, to achieve some level of uniformity and avoid drastically under/over-engineering subsequent systems?)
> but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
They understood it to be extremely risky immediately. They understood the ice issue early on as evidenced by the fact that they completely changed the coating on the external fuel tank to try to compensate for it. They also added ice bridges and other features to the launch pad to try to diminish the risk. They also planned for in orbit heat shield tile repair. They specifically chose the glue to be compatible with total vacuum conditions so they could actually detach and rebond a whole tile if necessary. They developed a complicated and, unfortunately wrong, computer model to estimate the damage potential of ice strikes to the heat shield tiles. What they _finally_ came to understand was that you just have to swing the arm out on orbit and take high resolution pictures of the vehicle to properly assess it's condition.
NASA was and always is very bad at calculating systemic risk. They have the right people developing risk profiles for individual components but they've never had the understanding at the management level of how to assess them as a complete vehicle in the context of any given mission.
> Roughly 3x riskier than the shuttle.
The huge advantage they now have is a capable launch escape system which can possibly jettison them away from the rocket should any issues arise during ascent. That was the one thing the shuttle could not possibly integrate.
On the other hand they could take a far larger crew to orbit and maintain them comfortably for several weeks during the mission. The "space bus" generated a healthy 21kW from it's fuel cells and created so much water that you had to periodically dump it overboard. This was a blessing for the ISS because you could bag up all that excess water and transfer it for long term use.
Anyways.. as you can tell.. I just really loved the shuttle. It was a great vehicle that was ultimately too exceedingly tricky to manage safely.
Glad that you are glad that they are safe and sound
An error in any of the orbital math may have seen them flung out into space with no chance of recovery.
Orbits do not work that way
The craft has aerodynamics and speed. It might be figuratively true "unrecoverable" but if it takes e.g. 2 weeks to complete a return, their oxygen and food and batteries ran out. Alternatively if it enters too fast they return ... in pieces.
I think you're being a pedant, if your point is a grazing entry causing rebound skip ultimately returns to some orbital path downward.
You seem to intentionally be ignoring the original quote that any error may have caused them to be flung into space. This is patently false unless the one math error is pumping in hundreds of pounds more propellant and burning far longer than the scheduled burns. NASA would need to make a significant series of mistakes beyond orbital math for the "flung out into space" statement to be true.
They certainly could've gotten the return wrong but with a perigee of 119 miles they arent even in a stable orbit and likely could deorbit themselves using only rcs thrusters at apogee, or by just waiting a few orbits.
This is underselling the risks. On top of the many trajectories which push them into unrecoverable situations, leaving them stranded in orbit, there can be trajectories where the moon gives a gravity assist strong enough to fling the spacecraft into escape velocity, fulfilling the OP.
In fact, the trajectory they chose for this mission exploited the opposite effect to yield a free return without propellant expense.
In the modern day, the chance of a math error being the root cause behind this failure mode are vanishingly small, but minor burn execution mistakes that do not require hundreds of extra pounds of propellant are definitely plausible. They were extremely common in the early days of spaceflight and plagued most of the very first moon exploration attempts. Again, with modern RCS this is unlikely. But reentry is still incredibly tight and dangerous. Apollo famously had a +-1° safe entry corridor, and Orion is way heavier and coming in even faster. If their perigee was off they could’ve easily burned up or doubled their mission time, which they may not have been able to survive.
The amount of things that would have to go wrong for the craft to get an accidental gravity boost and be ejected would be significant.
I feel like the original claim paints the whole thing as on a knife edge and barely achieved by virtue of not making a single mistake. In today's age with so many moon landing deniers and worse I feel like we should be specific about where the actual dangers challenges and unknowns there were here. In reality, the orbital mechanics are one of the simplest parts of the entire problem, at least when we're talking about a moon flyby
Yes, this is a fair point. I agree that orbital mechanics is trivially easy compared to everything else. The chances of a math mistake in particular are null, these trajectories have all been calculated years in advance.
The lumpiness of the moon's gravity is not well mapped out.
It is now better mapped after the GRAIL mission: https://en.wikipedia.org/wiki/Gravity_Recovery_and_Interior_...
The moon's gravity turns out to be "lumpy" because its density is not constant. This was detected by the Apollo missions and caused them to make errors in orbit calculations. This source of error could have influenced the flyby.
Anyone who has had hit period key once too many during Munar free-return in KSP knows it's exactly how orbits work...
Hilarious the the intellectual forum downvoted you for being absolutely right.
Artemis II never escaped Earth’s pull.
That video that NASA put out where the craft did a sling shop around the moon is extremely deceptive. The pull of the moon had very little effect.
If they had missed, they would have eventually crashed back to earth in the worst case, and best case just re-adjusted and returned a little bummed.
> The pull of the moon had very little effect.
No, it had a very significant effect: it's what made possible the free return trajectory while observing the far side of the moon.
Ok, but no not really. This is incorrect, the “free return” would have happened if they launched entirely in the wrong direction.
Like I said, the gif you saw makes it look that way.
Here is a link that explains it very well. https://youtu.be/MF8IbYbVIA0?t=269
I’ll agree, it seems crazy that it left earth, made it to the moon, and never really left earth orbit at all. That the furthest we’ve been away is still destined to return on its own.
> the gif you saw makes it look that way.
Makes it look what way?
Watch the NASA video carefully. It's clear that, even before the "loop" begins, Artemis is slowed down and is soon going to reverse direction relative to Earth. Which of course it would anyway, as you say--because, as the video you linked to points out, it doesn't have Earth escape velocity. The TLI burn gave it just enough velocity to reach the Moon's orbit with a little extra speed left over to get it about 4000 miles further.
But what would not happen without the Moon there is the "backwards" part of the loop--the part that took Artemis around the far side of the Moon. The Moon's gravity is what did that. In the Moon-centered frame in the video, yes, it looks like just a slight deflection--because that frame is moving with the Moon, whereas Artemis was moving backwards--in the opposite direction from the Moon in the Earth-centered frame.
Without the Moon there, Artemis would never have moved backwards, relative to the Moon's orbit, at all. Its trajectory in the Earth centered frame would have been a simple ellipse, with a maximum altitude from Earth a little higher than what it actually achieved (since the Moon's gravity did pull it back a little bit).
> This is incorrect
No, it's not. You aren't responding to what I actually said. See below.
> the “free return” would have happened if they launched entirely in the wrong direction.
But it would not have been a free return that let them see the far side of the moon, which is what I said. The Moon's gravity is what made that possible. And that was very significant.
> Artemis acceptable crew mortality rate is 1 in 30.
So with 4 crew members, chance of one dying was 13%! Very lucky they all survived.
> The Shuttle was risky, but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
I think they did think of it as risky and acknowledge that it was risky, they just had a different tolerance for risk.
The Artemis mission is "more difficult" - you're firing folk way out into space and hoping you hit a fairly narrow channel where they swing around the Moon back towards you, and not just keep going straight on out beyond any hope of rescue, or biff it in hard becoming a new lunar crater. You've got to carry a lot more fuel, and a lot more technology. You're going to have them up there in a much smaller space than the Shuttle for a lot longer.
The Shuttle by contrast was kind of "proven technology" by the end of its life, and we really should have developed some new stuff off it. Columbia first flew in 1981 but "the keel was laid" as it were in 1975! Think about the massive shifts in technology between 1975 and 1981, and then maybe 1981 and 1987.
I remember someone saying in 1981 that their new car had more computer power controlling the engine than took man to the Moon (the first time round!), and my late 90s car has more computer power than took man to the Moon in the instrument cluster. Your car is probably a lot newer, and has about as much computer power as NASA had on the ground for the Apollo missions just to operate the buttons on the steering wheel that turn the radio up and down, in a chip the size of your fingernail, that costs the price of a not very good coffee.
The main failure modes of space travel have always been "we can't get the astronauts back down", "we can't get the astronauts back down at less than several times the speed of sound", or "the astronauts are now a rapidly expanding cloud of hot fried mince". What's changed is the extent to which we accept that, I guess.
I’d bet a million dollars that Orion will win every safety metric compared to the shuttle once it is retired. NASA deluded itself in thinking the Shuttle was safe. The reality is that the Shuttle was the most dangerous spaceship anyone ever built.
That's physically not possible due to the distances and energies involved. Even with the Commercial Cargo and Crew Program (C3P), NASA has set the acceptable mortality threshold at 1 in 270 over the entire mission and 1 in 1000 on ascent / descent. If they could set it higher by gaming the math, they would. They can't.
We're a very primitive species, and the forces involved here are genuinely new. And no, Apollo wasn't much better either, at least 10 astronauts were killed in training or burned alive (8 NASA, 2 sister MIL programs), as well as (far worse, because astronauts sign up for the risk) one member of ground staff.
People love to hate the Shuttle, and it ended up being subpar / fail expectations due to the political constraints NASA was under, but the Shuttle was a genuine advance for its time – a nonsensical, economically insane advance, but still an advance. If you look at the Shuttle alternative proposals / initial proposals as well as stuff like Dynasoar and Star Raker, you'll see NASA iterating through Starship style ideas. But those were rejected due to higher up front capital investment at the time.
The Shuttle is an odd franken-turduckling, because it was designed for one mission and one mission only. And that mission never happened. That cargo bay existed to capture certain Soviet assets and deploy + task certain American space assets and then bring them back to Earth.
And that's the bit that's hard to emphasize. The fact that the Shuttle could put a satellite up there, watch it fail, then go back up, grab it, bring it back, repair it, then launch again was an insane capability.
Was the program a giant fuck up at the end? Yes. But does that mean Artemis will be safer than the Shuttle? No. That's not how the energetics, time from civilization, acceptable risk profiles etc. work out.
Shameless plug, wrote a bit about the Apollo hagiography, Artemis and risk here – https://1517.substack.com/p/1-in-30-artemis-greatness-and-ri...
It’s statistically unsound to compare results of low probability events like this.
https://en.wikipedia.org/wiki/Texas_sharpshooter_fallacy
How could a comparison between such dissimilar programs ever be meaningful? NASA flew 135 Shuttle missions over the course of 30 years; Orion will be doing well to approach a tenth of that number.
Space flight safety is a function of culture and I don’t have any confidence that the culture has improved.
I think we are a long way along from digging out Dr Feynman to look into why a shuttle exploded.
Unless you happen to have some deep links into NASA, in which case please elucidate us all, then why not celebrate a happy and safe return from a sodding dangerous mission that involved things like >25,000 mph relative velocity and some remarkable navigation.
When you depart earth (close quarters gravity, air resistance, things in the way), everything moves really fast, really fast and any acceleration becomes an issue really ... fast!
The moon moves, the earth moves: both famously in some sort of weird dance around each other and both orbit around the sun. Obviously the moon affects the earth way less than vice versa but it still complicates things.
I think that NASA did a remarkable job of making Artemis II look almost routine and I don't think that was down to behaving as they did in the past.
> I think that NASA did a remarkable job of making Artemis II look almost routine and I don't think that was down to behaving as they did in the past.
I have been excited for Artemis--yes it's big and expensive and late, but look how it has brought out the best of what humans can be--but, despite all that, the heat shield situation was textbook "normalization of deviance." Just as the O-rings were not designed to have any damage but they retroactively justified it was okay, just as there was not supposed to be any foam or tile damage but they retroactively justified it was okay, so too was the Artemis I heat shield not supposed to come back with damage, but they...
I'm not trying to be negative, and risks are inevitable, but the resemblance to me was uncanny. The lesson with normalization of deviance is that a successful result does not inherently mean a safe decision. After all, most of the time that you play Russian Roulette you will escape unharmed.
There will always be issues on something a mad as putting some people on a firework and shooting them at a moving target 100,000 miles away from a moving platform.
The heat shield failure was a test and the result was a working heat shield, when it counted. That's the point of tests. NASA already had several working heat shields from the old missions but the new one needed testing - for the shape of the craft etc. They already had a lot of data from the old efforts (that worked).
I think that exit and re-entry are almost routine now, provided your rocket doesn't explode. The tricky bit is out there in space and trying to make the moon a resource of some sort.
The new one failed in ways it was not designed to fail. In C-compiler terms it was "undefined behavior." In Donald Rumsfeld terms it was an "unknown unknown."
The mere fact that the outcome was successful does not inherently indicate that the decision-making was safe: the O-rings "worked" for 24 missions and the foam/tiles "worked" for 111. Nevertheless there were ample warnings and close calls.
Reentry from the Moon is not routine. Re-entry speed was about 40% faster than from low earth orbit, and kinetic energy goes up by the square, so about double.
Artemis rides on extended versions of the same SRBs that made the Shuttle ascent so dangerous.
Yes, and the four RS-25 main engines on the SLS rocket (Space Launch System) are literally SSME's harvested from the shuttles (Space Shuttle Main Engine). Of course that means they are re-usable. So sad to see them plummet to the ocean floor. Perversely Rocketdyne is building cheaper non-reusable versions of the RS-25 for future missions.
It has a launch escape system, unlike the shuttle.
Was any shuttle lost to the SRBs?
Yes, Challenger - although program management knew they were violating a launch constraint (temperature), and it was the low temperature that produced the conditions necessary for SRB failure.
As with any aerospace mishap, it's a chain of events, not just one cause.
Yes, challenger. The O-ring failed, creating a gas exhaust that almost instantly destroyed the main propellant tank.
I believe what it destroyed was the strut holding the booster to the tank. When the strut burned through the assembly came apart and aerodynamic forces did the remainder of the destruction.
Yes, 50% of shuttle losses were due to SRB failures (Challenger)
That's exactly how Challenger was lost.
The Artemis SRBs incorporate design changes to address the causes of the Challenger failure. Specifically they changed the joint design, added another o-ring, and they have electric joint heaters to keep the seals warm.
I mean it's the first space crew on an anti-science mission, right?
The point of them being there isn't discovery, it's to try to discourage anyone who wants try to understand and protect the planet that we all rely on for life
As an American I feel like I've been going through a bit of an identity crisis from what I remember growing up.
Probably the rose tinted glasses of being a child but being from Florida I always had a sense of amazement and wonder as I heard the sonic boom of the shuttle returning to earth.
Really felt like I was coexisting in this incredible scientific powerhouse of a country full of bright and enabled peoples that knew how to prioritize curiosity and innovation.
Feeling like a bit of a "vibe" post which is everything wrong lately but I can't help but feel some satisfaction that we're still able to accomplish something like this in our space endeavors.
I think especially online there's a lot of emphasis on "everything is wrong". A mission like this is hard to ignore and highlights the bias. On the whole, despite setbacks, we continue.
If you want to dispel a bit more of the ever-pervasive online pessimism bias, read up on global rates of hunger the last time we flew to the moon (1972) vs now. The reality is, for all the problems we face today, there's no sane answer other than today to the question "when would you prefer to be born as a random person on earth"
A global view is probably not the right way to look at things, encouraging as it may be. Of course globally hunger rates fell and so did child mortality. If nothing else, by the inexorable progress of science and technology.
But what about comparing the same country/region? After all that's a better sense of how things are progressing locally to you, and when people are asked "are things better or worse" they probably compare the way they live with the way their parents lived.
Would you rather be born in 1980 or 2020 in China? In Poland? No question. Same question but in the USA? In the UK? The West in general? I'm really not so sure.
Nope. Not from usa. I was born in 80s and would like to stay before 2000.
It is about trends and perceptions - 70s were very hopeful, now with global problems - wars, climate, AI, uncertainty, what is growing is desperation.
I definitely don’t envy kids that are born nowadays.
The '70s were not hopeful. Economy was terrible, Vietnam ended but still hung over the culture, Watergate, Three Mile Island, Iranian hostage crisis, cold war threatening to turn hot at any moment, double-digit mortgage rates.... and Disco.
Some parts of the US economy may have been terrible (perhaps due to the increased oil price, which became closer to the true cost of oil than that of the previous cheap oil, which was so cheap because it was basically stolen by USA), but in another parts of the world the economy was great in comparison with what followed after 1980.
Moreover, even in the US, the seventies were the greatest time for the electronics and computers industries, when the greatest amount of innovations have been made.
After 1980, there have been huge advances, but all of them were completely predictable, i.e. the electronics and computing industries settled on an evolution path that was well defined for a few decades, with very few surprises.
The seventies were much wilder, when much more diverse things have been tried (and many of those have failed) and they were surely hopeful, especially in their second half.
During the seventies, there were a lot of US companies that I liked and I was convinced that if I bought something from them that was mutually beneficial, because they really tried to make products that fulfilled as well as possible the needs of their customers, while ensuring a decent and reasonable profit for the vendor.
Nowadays there exists no big company in the entire world from which I can buy a product without feeling that this is an adversarial transaction, where they try as hard as they can to fool me into paying as much as possible for something that is worth as less as possible.
Patagonia is up there for me in current day. Let my people go surfing by the founder is a great read IMO
Definitely not the 70's. I think the most recent age that might have counted as hopeful was really between the fall of the Berlin Wall (1989) through the beginning of the GWOT (9/11/2001). So basically the 90's.
The seventies were a more representative time for technological hopes, during a time when it was not yet clear which are the right technological choices. The nineties were a time of rapid technological progress, but most of it was perfectly predictable, without surprises. The only thing that was surprising during the nineties was how important the Internet became in practice, even if the evolution of its underlying technology was not surprising.
The time correctly delimited by you was the time of the greatest false political hopes, when everybody around the World believed that we got rid of the communist blood-sucking parasites and now the World would become that which had been described for decades in the propaganda of the Voice of America, where the political elites are held accountable for their actions, so if they are bad they are replaced through democratic elections, and the bad commercial companies are eliminated by competition in the free market.
Instead of this happening, already a couple of years before 9/11 a wave of destructuring many important historical companies happened, followed by a huge wave of mergers and acquisitions that has continued until today and which has eliminated competition from most markets, so that they are now dominated by quasi monopolies. Then the democratic elections have brought to power worse and worse human beings, all of whom have been much worse than some citizens that would have been randomly selected for those positions.
Nowadays, the economies of USA and of the other "Western" countries, and also their political institutions, resemble much more those of the socialist countries that they mocked during the seventies, than those of USA and W. Europe of that time.
So all the hopes of the nineties were naive and none of them was realized.
> The '70s were not hopeful
Civil Rights Activists protested against Apollo 11 at the Kennedy Space Center in 1969, and "Whitey on the Moon" was released in 1970.
The Father of Disco was involved in the song "Electric Dreams" associated with a film about AI in a love triangle.
Have you checked the news recently?
There's a lot of money/hay/political power/etc to be made from "everything is wrong" - it's hard for "good news" to really get into your bones.
Not to say it's the best of times, nor to say it's the worst of times, mind you. Just that it's really hard to objectively compare.
Many of those who saw the first moon landing as a child are still alive and remember what it felt like.
From one of the ground staff for Artemis: https://bsky.app/profile/captnamy.bsky.social/post/3mi36brfw...
"1968 and the country was on fire. Vietnam. Assassinations. Civil unrest. Protests.
Apollo 8 was the one bright event of a terrible year.
2026 and the country is on fire. Iran. Corruption. Fascists. Civil unrest. No Kings.
I hope Artemis II will stand out as a bright spot for our country."
Some more background on her: https://chicago.suntimes.com/news/2026/04/01/chicagoan-amy-l...
The nice thing about a public space program is everyone can share in its success!
I had to explain to my wife and kids (not that I'm in this field, but I also have to remind myself) that we are able to pinpoint where the craft will land, when it will land down to the minute, because of ... just ... math. And we're able to get them there and back because of science.
It all boils down to equations that describe the world accurately, and a way of experimentation, iteration, thinking that gets us all the way to do something this unbelievably complex.
The analogies for these things like "hitting a golf ball into a hole in one 5,000 miles away" are always fun.
I like starting from the fact that Ptolemy was able to get the accuracy of the "motions of the heavens" down so well that it took more than a thousand years to get observations that showed discrepancies. The math, it maths.
I always feel like these analogies don't really fit the real space flight as you quite often have a lot of time to correct the trajectory if you get it roughly right during launch and even that takes a couple minutes. You also have closed circuit guidance and external radar stations to verify the trajectory.
You really don't have anything like that when playing golf, so I don't thin it is a good analogy.
But for the old Sprint anti balistic missile - that was spot on. :D Hitting ICBM warheads kilometers abobe ground, second before detonation - yeah, that fits. It also dispelled the myth that you can't communicate to compact craft due to re-entry plasma. Of course you can, just use a 30 MW radar beam & it will get through just fine! Not to mention the Sprint missile was protected by an ablative heatshield and covered by plasma going up during launch. :D
There’s a big difference (not really as much as you might think because fuel is limited) between a single shot with no thrusters and a rocket that has all sorts of adjustments possible.
It’s all in fun, really, like the old analogies involving hard drive heads and jet planes.
I feel like it’s “easier” with space math because there’s so little to interfere with the course. With a golf ball, the basic math is easy, but the slightest bit of wind throws it off way beyond the acceptable error, and you can’t model all the wind perfectly.
The first-order approximations are easy. When you start adding up all the other factors, it gets complicated fast. The solar wind, which isn't constant, affects trajectories. Earth's atmosphere is neither homogenous nor perfectly predictable along many dimensions: upper-level wind speeds and directions, air density, and temperatures, to name a few. The Moon's gravitational field is very lumpy. Earth's gravitational field, while relatively smooth compared to the Moon, also isn't perfectly uniform. Propulsion systems have tolerances. Same with parachutes. The location of the vehicle's center of gravity affects everything.
All of these factors and more have to be taken into account if you want your predictions to be accurate. Aside from telemetry processing, most of the computing power on the ground during a space mission is used for churning out navigation solutions.
Agreed.
Fun info: The NASA orbital codes include things like photon pressure... from sunlight reflected off of other planets in the solar system. At some point, I think they are just showing off :)
Not a great analogy because there actually is interference and golf balls aren't typically monitored and course corrected during flight
I'd add a caveat to this.
We can do this because of war.
We know where it will land accurately because that maths and physics has been sharpened with butt loads of data. Even the reentry blackout has links to war in Plasma Stealth[0].
That data was mostly obtained because we want to know where our ICBM warheads will land. And where the enemies ICBM warheads will land so we can work on the problem of shooting them down.
The Russian Kinzhal missile can hit targets at mach-10, with a plasma aura making it's terminal phase hard to track on Radar. But after some data was collected Patriot missile systems were able to intercept about 1 in 3 air launched Kinzhal missiles. Then minor terminal adjustments were introduced and interception fell to about 1 in 20. Now there's a constant cat and mouse game going on in Ukraine.
On the one hand that's a good thing, our combative efforts being sublimated into curiosity of the world.
On the other hand, we still put far more effort into furthering our ability to destroy the world.
[0] https://en.wikipedia.org/wiki/Plasma_stealth
IIRC reentry plasma is actually highly radar reflective - so it is not hard to track, just hard to hit due to the speed, as there is limited time to do it.
If that were the case then the mach-10 Kinzhal would be harder to hit than the mach-5 Kh-32.
But the interception rate for the Kh-32 is basically nonexistence (<1%).
The Kh-22/32 is why mach-5 + maneuverability is the current goal of offensive missile systems.
The plasma has complex interaction with radar, it's not stealth as in entirely invisible just chaotic scattering and reflections. The result is a jamming effect preventing a definite intercept solution.
On the other hand the plasma shows up on satilite based IR tracking systems.
To say “because of war”, you would also have to prove we could not do it without war.
That's an absurd statement. By your logic, you can't just say that we have the smallpox vaccine "because of Edward Jenner". Because you would also "have to prove we could not do it without Edward Jenner". What does that even mean??
Has NASA (or anyone) said anything about how the heat shield performed?
Wild that they manage to fly to the moon but still seem to be having those comms problems. Asking the astronauts if they’re really pressing the PTT button is wild.
My friends and I have been deriving much amusement from the comms issues. We can fly people around the moon, talk with them, send back high res video, but talk to the boat that’s close enough to swim to? Forget about it!
Note: next time, pack a walkie talkie. ;-)
No joke, VHF has been saving sailors' lives for a long time now.
They missed the chance to reply "Main screen turn on."
Siri turn on main screen
Just like in the year 3000, we will still ask "Can you hear me?" in video meetings.
And the printer will be perpetually broken
I can see your comment, can you see mine?
"Can you see my screen?"
grrr
This is the same mission where the commander radioed to Houston, “I have two Microsoft Outlooks, and neither one of those are working”.
i was thinking maybe astronauts can be disoriented when splashing down and that's why they figured they should ask if the right buttons were being pushed?
Cellphone coverage notoriously flaky in the Pacific.
Umm it's a satellite phone.
...and informing them which button was the PTT button. She had to say it, but it'd be hard not to react to that.
I give you Apollo 16:
https://www.youtube.com/watch?v=Uuv6TVv0r44
Good thing they have redundant systems.
This whole mission was amazing, and the most positive and hopeful thing I have seen as a global event in the last 5 years at least. Bravo and cheers to everyone involved :)
Apparently there's more work than just clicking "Recover Vessel" after splashdown!
1 hour 29 minutes seems excessive to extract the astronauts; if any of them _did_ have a medical issue they'd be in for a long wait.
The commentary said that the initial problems with the boats approaching Integrity was due to an unexpected swell. Unexpected, in the Pacific?
Edit: all of the Apollo missions, except 8, had their stabilization collars inflated in under 20 minutes. With Integrity today it took nearly an hour more.
I imagine if there was a medical emergency they'd worry less about capsule recovery and safe shutdown. IIRC because the sat phone wasn't working, they had to wait an extra 15 mins to power down the capsule (I guess so they could use its radios?). In an emergency I imagine they'd just leave it as-is
I also like how they waffled on about how winching them up to a helicopter was the fastest option, when they obviously could have shaved an hour off the recovery time by simply having them step out onto the waiting boats!
Having worked for various government agencies for a while I've learned to recognise the signs of the "We're following the procedure whether it makes sense or not, dammit!" attitude you get with large bureaucracies.
I wondered about that. Winching someone who can barely walk and is wearing a spacesuit into a helicopter over choppy water is safer and quicker than parking them on a motor boat and sailing back to the mothership?
What was the real reason? Tradition? Lack of imagination? Photo opportunities?
The rest was great tho.
So someone who can barely walk is supposed to safely jump from a space capsule to a boat in the middle of the ocean?
To play devil's advocate against my own argument: The nearest ship was about 5 km away, which is a decently long boat ride. In choppy waters with a small boat that could be less than ideal for someone who may be injured, weak from an extended stay in microgravity, etc. I assume the plan -- written months or years before the landing -- also had to factor in the possibility that the ships wouldn't have been so close. They did mention several times that the landing was unusually accurate, so it is entirely possible that their pre-planned helicopter ride would have made a lot more sense if they were, say, 20+ km away instead. You don't want dozens of people improvising the procedure in the middle of choppy waters with bad comms, so the best thing to do is to just follow the plan, even if it looks a bit absurd on camera.
Is 10 days enough to make walking difficult?
“Stepping” from one vessel to another in the middle of the ocean is not like getting on your buddy’s sailboat at the marina even if you have your sea legs. Astronauts don’t even have their earth legs when they splash down; when they return from ISS they can’t even walk right away, though Artemis was a shorter duration mission than that.
Uh yes. Doing space missions is dangerous and unexpected things can happen.
Watching this, I can only describe it as holy. An incredible reminder of what humanity can do, and the beauty of our curiosity and the universe around us. I grew up learning that my great uncle was in Mission Control for Apollo; missions like this are what inspired me to pursue engineering in the first place.
It’s been amazing - and inspirational - watching the live stream of Mission Control and the capsule over the last ten days. Or at least having it as background audio. I’m going to miss all these folks I’ve grown to know.
Bring on Artemis III and IV!
Impressive mission but I feel it's not capturing the public attention because it's actually a step back from the mission 50 years ago when they actually landed men on the moon with tech that was orders or magnitude simpler and less powerful.
I've noticed there's a pretty big difference between the people who remember how routine shuttle flights became and the younger crowd at work. I do think Artimis is cool, but I will admit to being a bit jaded about it as a GenX who watched Challenger live in 2nd grade. The GenZ at work seem genuinely delighted. And that's pretty cool.
A diverse and inclusive crew, a publically-funded mission, an emphasis on science and discovery, and government investment in a long-term strategy, not a quick politcal win.
This current administration has made sure these things never happen again, Artemis is very much the swan song of an America that has died. I am not interested in watching our corpse twitch and calling it life.
I think it you ask the average person they're more surprised that people haven't been going to the moon for the past 50 years. In people's minds it's a solved problem and it's been boring for decades now. If supersonic air travel came back it would only interest people because of reduced journey times. But this doesn't even have anything that directly benefits people so they don't care.
"NASA reporting four green crew members. That is not their complexion, it is that they are in good condition. That's what that means." LOL
also astronauts: "the moon is quite a bit smaller than it was yesterday"
control: "i guess we'll have to go back".
(paraphrased from memory)
The humor was what really made my day today. Or in my case my night here in Germany.
I guess they're not Kerbals :)
That speaker voice was a bit odd. Everything was perfect! At least one superlative every 5 seconds or so.
I think that audio stream was designed to be POTUS safe.
If we're going to have a surveillance state, let's use it for superlative control - one dollar in taxes for every superlative you use in personal life; $0.01/viewer for each one you use in any live televised event.
It's becoming a public hazard, we must act!
Agreed in principle. Let’s make things norminal, not superlative.
Held my breath the whole time after all the heat shield warnings. Very glad it all worked, or that there was enough margin!
Yes it was worrisome, but how could it not be even with the best tech we'll ever have - I feel relief still on every plane touchdown.
Bravo, Artemis team for an exceptional return to extra-orbital space travel.
The LOS was also more than 6 minutes as predicted (I measured a bit over 7 minutes). What a tension.
I wasn't clear, was the LOS just comms or a full loss of telemetry from the craft? Either way, terrifying.
Everything. No radio signals make it in or out of the capsule due to ionization from the heat and plasma of reentry.
I’ll note, since it is supremely interesting to me, that Starship is able to communicate with the ground during its whole reentry due to its sheer size and ability to connect with Starlink satellites. I assumed loss of signal due to reentry was a given for any spaceship!
Shuttle in its last days had antennas that protruded outside the plasma just enough for telemetry. Apollo and Artemis reentry are also direct entry from Lunar-Earth transfer orbit using ablative heat shields, so the plasma would be hotter and thicker than suborbital Starship shots with Shuttle style ceramic tiles.
I'm pretty sure it did not stick anything through the plasma sheet- that is impossible. You would eithe melt the thing or just shift the plasma sheet a bit. It forms as air is compressed on contact, simple as that.
What IIRC was actually done was that some antennas were placed on the back of the shuttle & its size was big enough that the plasma bubble would not fully envelope it - it would be open up to space. And that antenna on the back would communicate with TDRS satellites through this gap, enabling contact through the whole re-entry.
Starship does basically the same, just with Starlink satellites instead of TDRS.
Would this capsule had been been able to communicate if it was integrated with starlink or is the size more important? I'd imagine if they could have achieved communication via Starlink they would have done it, but just curious.
It's a function of the shape. On a capsule-sized spacecraft, the ionized plasma completely surrounds the craft, so no radio communications can get in or out. For an oblong-shaped spacecraft, like the Space Shuttle or Starship, the descent tends to be angled such that you have a "hole" in the plasma you can get a signal through.
No, the plasma forms a teardrop shape around small craft like Orion, completely cutting off radio comms. Larger craft like starship or the shuttle which have a roughly cylindrical shape (vs Orion’s circular cross section) aren’t fully enclosed by the plasma. The shuttle had a transmitter attached to its tail for later flights, which could send back telemetry during re-entry.
Well, provided you had a 30 MW microwave transmitter on board, you could punch through the plasma just fine, it has been done:
https://en.wikipedia.org/wiki/Sprint_(missile)
"Sprint accelerated at 100 g, reaching a speed of Mach 10 (12,000 km/h; 7,600 mph) in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,400 °C), requiring an ablative shield to dissipate the heat. The high temperature caused a plasma to form around the missile, requiring extremely powerful radio signals to reach it for guidance. The missile glowed bright white as it flew."
Awesome, thank you! I wonder if some kind of very long-tethered deployed antenna could enable this for the capsule or if the ratio of long-enough-to-work vs thick-enough-to-not-burn-off-completely just doesn't work. Time to read about the shuttle.
It's the shape and size.
Also Orion and other capsules fall like a rock (steep reentry profile ) compared to shuttle/starship, which intentionally slow down the reentry and kinda glide (ballpark 10min with capsules compared to 30min with shuttle/starship).
tl;dr: capsules get fully enveloped in plasma due to their shape, size and reentry profile
The space shuttle, too, was able to communicate. I imagine the smaller the craft the smaller the angle you can "speak" out of and, below a certain size, it just doesn't work.
Yes, I remember when they used the signal out the back through the plasma during reentry. It was astoundingly good!
It seems like they had limited telemetry for a short period before they did any audio
I was wondering about that, so I looked up the heat shield issues. It seems like their solution was very defensible and there was every reason to believe it would work out just fine. The plan that did not work as they wanted had a new idea, a double re-entry, and when the results were concerning they backed off to using a traditional single re-entry. That seems like a legitimate fix?
Scott Manley went into the details in a recent video.
The reason the heat shield failed was due to gas buildup inside the ablative material. This was due to the skip reentry profile they used, where the craft does a single skip (as in skipping stones) during reentry. The high bounce caused the shield to be heated enough that the heat penetrated the material causing gas release but not enough that the material ablated. Thus gas would build up deep inside up until it caused large chunks to break off. They could reproduce this in tests.
The fix was two-fold. First they lowered the bounce height, so a much less pronounced skip, avoiding the lowered heating of the shield. And they tweaked the material formula a bit so it was more porous, allowing subsurface gas to escape rather than build up.
No doubt there are people looking at the heat shield right now and saying "Hmmm."
I am very curious about what they're seeing, and how well the get-it-over-with solution worked.
It was a bold move and the results will be fascinating.
In my understanding of the Manley video, the materials change will only occur for Artemis 3, for which it will be irrelevant as that will not be leaving LEO.
Yes, but it was the biggest opening for propagandists to latch on to for demoralizing and spreading fear/uncertainty/doubt about the mission.
Same! Glad everyone made it safe.
Can somebody help me understand why this does a water landing, like the old Apollo missions, instead of like the space shuttle that lands like a plane?
A big part of the reason is that Orion (and Apollo) reentry speeds are way higher due to the orbital mechanics involved in going to the moon and back. Today's was actually the fastest manned reentry ever attempted.
For reference the shuttle generally reentered at ~17.5K mph, and today's was 24K-25K mph.
It's not clear that we could build a craft with wings that could survive that. So then you're looking at adding fuel just to slow down, plus fuel for the weight of the wings themselves, plus fuel to carry all this extra fuel to the right place, etc.
The space shuttle landed like something resembling a plane, but it is more accurate to say it landed like a concrete brick traveling faster than the speed of sound.
Splashdown-style landings are the simplest and safest, parachutes are always good but adding water makes for another layer of safety (and of risk, to be fair, it could sink).
Wings and rudders and landing gear are very heavy. Then there's the flight control system in all its complexity, along with redundant hydraulic systems and so on.
Lot of the world is ocean & they basically decided the landing point the moment they entered the free return trajectory, 9 days prior - easier to shift the landing point a little to a different place in the ocean place with better weather tha. to switch to a backup airport.
With lunar landing flights they would still have to choose 4 days before, as long as they do direct return.
Eventually you want to break to Earth orbit (propulsively or aerodynamically) and board a dedidacted craft for landing. But till then water landing capsules work.
A Space Planes is needed to land at a runway like a plane.
Space Planes are not only much more dangerous, but are not ideal for this type of mission. They carry a lot of extra weight (wings) that would affect how much fuel is needed to launch them to the Moon.
Capsules are safer and more lean in terms of weight.
The Shuttle was not ideal in many ways. It was used so long not because it was the best option, but because Congress wanted it to keep it going for jobs.
Buoyancy is an easier equation to solve than lift.
So why do they need to use helicopters and a risky airlift to return the astronauts to the main vessel? Why not just use the speedboats to take them back? Seems really odd and I can’t find any reasonable explanation.
Helicopter -> large boat is much easier, and much faster, than small boat -> large boat. And it's not riskier. I know the inherent risk in flight is greater, but it's also much more managed, so the actual risk is less.
>Why not just use the speedboats to take them back?
They actually covered this in the broadcast: Helicopters are faster to get the astronauts to medical, smoother in rough seas, and there's less risk of being swamped by a rogue wave. Plus, since the astronauts might have fatigue/muscle atrophy/whatever, it complicates potential boat transfers.
The public information sheet implies that in poor weather/rough seas they would do crew recovery in the well deck, sort of like how Dragon works. [1]
From the broadcast, they made it sound like a big factor is the 2 hour program requirement to get the crew out of the capsule. Maybe they can't reliably hit that mark with a well deck recovery?
[1] https://www3.nasa.gov/sites/default/files/files/orion-recove...
>Buoyancy is an easier equation to solve than lift.
That's a snappy one-liner but it doesn't address the real concerns.
First of all, subsonic lift is well understood and has been for decades. The answer is much more mundane: The Artemis mission profile does not require payload doors that open, no Canadarm, no requirement to service, launch, and/or capture satellites in orbit, and so like good engineers they designed the minimum vehicle that satisfies the requirements.
Also, the Shuttle was actually much more expensive to reuse than originally predicted.
> subsonic lift is well understood and has been for decades
I said easy. Not well understood. I can fly planes. It’s hard, and has limited room for fucking up. (It’s also hyperbole to suggest we understand lift. We don’t.)
Piloting a boat is easier and more forgiving. Hence, splashdown. You don’t need direction. You don’t need lift. Parachute physics is a backbreaker, but it’s symmetrical. Same for splash.
You're a VC arguing with an aerospace engineer about aerospace engineering.
I'm also a pilot (CFI). My day job is space operations. And I can tell you've had too many hangar arguments about how wings work.
Pilots don't understand lift. Aero engineers understand it just fine.
I love this comment. Thank you. For what it’s worth, I’m not a CFI but I did study actual astronautical engineering. Not much good once we’re in an atmosphere, which, granted, is where the boats and planes go. But I’ll stand by my statement that nobody—apart from interplanetary reëntry and drone teams—fundamentally understands lift. (I certainly didn’t when I was solving analytic solutions by hand.)
>Piloting a boat is easier and more forgiving. Hence, splashdown.
At no point were the astronauts piloting a boat. The reasons they splash down into the ocean has nothing to do with buoyancy being easier to solve, and even less to do with the ease of piloting a boat.
>It’s also hyperbole to suggest we understand lift. We don’t.
Maybe you personally do not understand lift, but "we" do in fact understand it. Please educate yourself before continuing this discussion any further.
There are multiple mathematical and physical approaches to understand lift, but they have the same results and are correct.
Aerospace engineer here: The simple answer is that the Shuttle form factor is unnecessarily complex for this mission.
A small Apollo-style capsule that parachutes into the ocean has a simpler mission profile, which allows for simpler technical and operational requirements, which in turn reduces program cost.
Too fast. The space shuttle used to reenter sometimes over us in California. I remember in elementary school the entire building shook, and that was just one building! The amount of energy being dissipated is literally astronomical! If you've never experienced the sonic boom of reentry it is something to marvel at. It literally feels like an earthquake!
Watching that capsule fall out of the sky at high speed from the teaching cameras was nerve wracking! Awesome footage, exciting to watch it live in such detail.
What is coming into view from the top center at 08:26:25 [0], right after the commentator says, "the weather conditions remain go"? It stays visible for more than seven minutes before disappearing behind the horizon.
[0] https://youtu.be/X9Miy8ngusQ?t=30382
The Moon.
Interesting.
I had this in the back of my mind today https://idlewords.com/2026/03/artemis_ii_is_not_safe_to_fly....
Glad they got home safe and sound!
Not for the same reason as you, the whole time I was thinking "I'm pretty sure NASA can assess the risk of their mission better than an Internet famous blogger", despite the sentiment on HN at the time being very negative after reading these words [1].
These days the only qualification required for people believing anything you say is to have a blog and strong critical opinions about $AUTHORITY. Software engineers somehow believe they are knowledgeable in any topic just because they spend a lot of time reading on the Internet.
1: https://news.ycombinator.com/item?id=47582043
Announcer just said “we just reenacted” the last Apollo mission. So, yep. That’ll be used as proof-text that this was all staged.
I get that there are people who think the moon landing was staged, but are there really people who think rocket launches are staged? Because it's pretty easy to go witness one yourself.
The fools who would believe that wouldn't believe Apollo happened either. No need to dignify their existence.
Apropos
https://www.youtube.com/watch?v=jG6NNnoNC80
For All Mankind aired an episode today that movingly commemorated the fictional lead character Ed Baldwin's Apollo 10-like in-universe mission on the same day that the real world Artemis II mission which also strongly resembles Apollo 10 landed safely. A strange and moving coincidence.
Buzz Aldrin is reported to be watching this on TV.
Dealing with the typical Excel foot guns during the last few hours before re-entry felt like an unnecessary risk.
Missaved their version 2 Excel spreadsheet using the wrong file name causing confusion about this version was the latest.
Nearly missed a cell in their burn sheet had multiple lines of text until mission control reminded them to resize the cell.
Ad astra per aspera
Amazing, congrats! Why where they hoisted by heli and not ‘just’ sail to the mother ship (and hoisted there)?
So the new heat shield works just fine, and NASA still knows things better than arm-chair aerospace engineers? Safety third.
It's hard to know who was right. All of these things can be true: it made it back ok; it had a high chance of making it back ok; it should've had a much higher chance of making it back ok. Most of the concerned people were stressing this last point, that it should've been safer than it was. They still thought it had a quite high chance of making it back ok. It took a lot of shuttle missions before Columbia failed.
While I agree with your main point (it's hard to know who was right), the people who agreed to proceed were NASA engineers/astronauts who had actual numbers to analyze, while the doubters (even Camarda) only had theories.
We'll need a post mortem to know what the margin of failure was. This said they had made changes since the first flight so we'd expect less to no damage this time.
Awesome! I can't wait to watch the moon landing whenever that happens.
This almost brought tears to my eyes. I can only imagine how people felt when the first astronauts got to the Moon, and then when they got back to Earth in one piece.
Cheers! Looking forward to future space travel!!
Woke up at 5:00 am to watch this live Regret no part of it
"Reid Wiesman reporting all crew members green; that's not their complexion, all crew members are in good shape."
Dammit. I hoped Jeb was on board for a second.
Bravo Zulu, Integrity crew, NASA, and USA!
Been a long time since I've felt any amount of national pride like this. Welcome home.
With 1 in 30 chance of death can somebody help me understand why this had to be a manned mission?
Has anyone collated the best space based footage?
Millions of people are going to bed hungry and yet here we are spending billions on stuff like this to please elites ego
Do you think the billions spent disappear into space? It pays the salaries of everyone involved so they can eat.
Let's feed millions for free so they can breed billions who must be fed.
Amazing live video of the descent and splash down. Really awesome to watch!
Went out to the beach hoping to hear/see something, but sadly grey skies and no boom. Tons of other people out there doing the same thing too.
I noticed a delay between video and audio - the announcer on the NASA official live broadcast said splashdown before the the capsule splashed down on video. Was it intentional (in case something happened)?
Also, what were these puffs on thermal camera after the main chutes were deployed?
https://www.youtube.com/live/m3kR2KK8TEs
My suspicion was they were burning excess propellant, rather than attitude adjustment while under the parachutes. Though who knows how much propellant remained. It could be quite a bit more than it appears was used.
Not just excess - excess and toxic. Hydrazine derivatives and nitrogen tetroxide, IIRC. They are hypergolic, too, so the easiest way to vent them is just to run the engines until empty. However, to prevent moving the craft too much, you do short bursts.
On the press conference they mentioned the RCS was used to orient the craft with the most sturdy part facing down for the ocean impact.
Otherwise I would also just bet on RCS venting like in Apollo.
There should be an opposite thruster for each axis. I wonder if the short bursts were due to heating limits.
There are opposed thrusters, but I assume that in atmosphere and under parachute canopy it’s harder to make sure they are perfectly opposed.
Heating likely plays a role as well.
I am not a rocket engineer, but I have read How Apollo Flew to the Moon and Ignition!: an informal history of liquid rocket propellants, both of which cover these issues. Highly recommended.
The short bursts are just the period of the control cycles. Control cycle starts, loop sees error, commands thrust; next control cycle starts, loop sees error is nulled (or in deadband), commands no thrust.
In the post splashdown conference, they mentioned that these were indeed attitude control bursts to orient for favorable orientation for water impact.
It was for attitude adjustment.
RCS (Reaction Control System) which you can see on Artemis I internal video as it falls down https://www.youtube.com/watch?v=-QbYrs5SZ5M
I was wondering about that too, I assume maybe there was some additional adjustments needed to land in the right spot, but they didn't mention it on the stream.
Yeah, they looked intentional - there are no reaction wheels on the capsule.
good, But how did you build it?
Now this is actually for the benefit of humanity.
…and this is how the America I thought I knew growing up projected its influence upon the world.
Notwithstanding that this mission critically relied upon Canada, UK, EU, Japan, Taiwan, and contributions from many other countries.
Collaboration like that is all a (positive!) part of projecting influence - in both directions.
All those countries are essentially American vassals. No shade to them, just stating the reality, and not really sure why we need to keep pretending. There's no shame in that. It's often the smartest move to join forces with the big guy in the block!
You need to travel more.
At least now there’s something to celebrate for America’s 250th this year
How? I struggle with this. It all seems like a fearful waste of money and resources. We can't live on the moon. We can't live on Mars. It is a fantasy. We have so many problems here on Earth that are more important to solve than sending a handful of men to the moon (again).
Same things said about a lot of things. Tech works. Human ingenuity works.
As I've said before. This is a huge achievement. And also is the most effective political propaganda ever. Bravo to everyone involved .
This is not sarcastic. This is very much meant. I love that America does this. We still get to evoke an awe which previous empires awesome as they may be, could never match. American superlatives are amazing. God bless America
I don't know how to describe the feeling but it feels like a bad movie remake. Maybe I am just a sucker for practical effects and not 2020s CGI to stick with the metaphor and conspiracy...
In 2028, so only 2 years from now. They will be able to bring 4K pictures and videos of the walk on the moon and they promised not to delete them this time.
They will have Nikon cameras, GoPros, and iPhones with them.
Very different from the videos taken with the Gameboy Camera.
As a long time space nerd, I'm not sure what this accomplishes by repeating the previous stunts that failed to usher in the promised space frontier.
Apollo was, IMO, not successful at changing the course of human history. A really cool footnote, sure, but everything else that was to follow, nope, just a bunch of neat, interesting but ultimately meh science missions.
An exciting change would be more like Delta-V/Critical Mass, but NASA is not going to deliver that, at least not in any form it has taken thus far.
The guidelines ask us to avoid being curmudgeonly. I'm sure you didn't mean to come across that way, but could you try not to make Hacker News the kind of place that responds with “meh” to a successful space mission?
My pessimism comes from a hindsight that the Apollo missions, while amazing failed to create the future they promised. Looking at how the missions were designed, the political focus, the academic infighting of NASA scientists trying to keep niche research funded. I fail to see how this time, the same strategy will produce a different result.
I also don't expect benevolent billionaires to fill that either. I hope I would in their place, but I'll not likely get the chance.to find out.
To end on an optimistic note, tang and Velcro are pretty dope.
I blame the "space race" narrative - it made everything unsustainably expensive just to beat the goal of landing on the Moon by the end of the decade and before the Soviets. That also made the program even more dependant on political whims and easy target for budget cuts in the Vietnam era.
I recommend looking into the space flight plans from the pre Apollo - while tere were bonkers ideas like Project Horizon, most of the plans sounded quite sensible, with incremental building of space infrastructure and emphasis on cost and reusability (in the 1960s).
Of course when it became a race all the sustainability and infrastructure went out of the window and got sacrificed in the name of speed. :P
We can't build a TV from 50 years ago, much less a space rocket.
Because we stopped, we get to do everything over again with hardware from this century.
My point is this path doesn't lead to the future, it leads to the sad state of space between Apollo and this Shark Jump.
The first Orion (nuclear pulse) has a much more interesting story and would have made us an interplanetary species before we had the iPhone. But it was killed by Kennedy, became space wasn't what he was worried about.... And maybe hundreds of nukes in space might make some countries edgy.
They can't just build Apollo 18 and resume the program as if there weren't a 50 year hiatus.
Imagine if your employer wanted to start using a software system it retired in 1972. What would you do?
Just another monday in any big old company adjecent to finance or airline industry ? ;-)
What is delta v/critical mass?
Dear NASA. Please dial back the poetics and rhetoric. Be more like ATC than Shakspear.
I think we've all become to numb and jaded. This is the first moon mission in 50 years and the furthest any human has ever been from Earth.
Indeed, the world is so grim these days that I welcome even a little bit of relief, a little bit of hope for a better future.
More than that, people today seem to be saturated with sarcasm.
It's especially tragic with younger people who seem to have no experience with handling genuine sincerity. They laugh nervously at it, as if they're unfamiliar with how to handle someone saying what they actually think and feel.
It's fully scripted. The hokum is pre-planned.
The questions from the news agencies and their responses are not scripted. I encourage you to listen to the Q&As the astronauts and ground crew had during the mission and judge their character on that. You won't find any public figure / politician with any amount of media training that even comes close to their level of genuine humanism, humility, and professionalism.
Hard disagree. Yes it is corny for us oldies but channel your 12yo self watching Cosmos.
I read "Shakspear" as a combination of Shaquille O'Neal and William Shakespeare.
To dunk or not to dunk.
I’d pay to see Shaq on broadway.
Someone hasn't stayed awake all night listening to YouTube ATC. I recommend Kennedy Steve.
Thanks for the tip!
What a curmudgeon. You must be great dinner company.
Best comment exchange from a thread on a different site:
OP: "I'm happy they didn't die."
Response: "You're going to be less happy when they turn into the Fantastic Four and Dr. Doom shows up."
Why this was such a big deal? Haven't people reach the moon so many years ago? By this time we should have lunar bases, not cheer so much that we got past the moon at a few thousands miles away.
Because we haven’t had translunar manned flight in fifty years, and this is the precursor to start it up again