I haven't kept up with Artemis development but I've read extensively about Challenger and Columbia. These two parts of the article stood out to me:
> Moon-to-Mars Deputy Administrator Amit Kshatriya said: “it was very small localized areas. Interestingly, it would be much easier for us to analyze if we had larger chunks and it was more defined”. A Lockheed Martin representative on the same call added that "there was a healthy margin remaining of that virgin Avcoat. So it wasn’t like there were large, large chunks.”
Followed by:
> The Avcoat material is not designed to come out in chunks. It is supposed to char and flake off smoothly, maintaining the overall contours of the heat shield.
This is echoes both Shuttle incidents. Challenger: no gasses were supposed to make it past the o-rings no matter what, but when it became clear that gasses were escaping and the o-rings were being damaged, there was a push to suggest that it's an acceptable level.
There was a similar situation with heat shield damage and Columbia.
In both cases some models were used to justify the decision, with wild extrapolations and fundamentally, a design that wasn't expected to fail in that mode /at all/.
I know the points that astronauts make about the importance of manned space exploration, but I agree with this author that it seems to make sense to run this as an unmanned mission, and probably test the new heat shield which will replace the Artemis II design in an unmanned re-entry as well.
I've often thought world leaders, upon election/selection, should get a free few orbits of the earth, to give them some perspective on the job they're about to undertake. Maybe offer the first one on Artemis II, a deferred one for the current US administration?
Camarda is an outlier. The engineers at NASA believe it is safe. The astronauts believe it is safe. Former astronaut Danny Olivas was initially skeptical of the heat shield but came around.
And note that the OP believes it is likely (maybe very likely) that the heat shield will work fine. It's hard for me to reconcile "It is likely that Artemis II will land safely" with "Artemis II is Not Safe to Fly", unless maybe getting clicks is involved.
Regardless, this is not a Challenger or Columbia situation. In both Challenger and Columbia, nobody bothered to analyze the problem because they didn't think there was a problem. That's the difference, in my opinion. NASA is taking this seriously and has analyzed the problem deeply.
They are not YOLO'ing this mission, and it's somewhat insulting that people think they are.
If you play a single round of Russian roulette with a revolver, it is likely you will not die, but it is also not safe to do that. The same idea applies here.
The foam shedding/impact problem was heavily analyzed throughout the Shuttle program, and recognized as a significant risk. Read the CAIB report for a good history.
That report also describes the groupthink dynamic at NASA that made skeptical engineers "come around" for the good of the program in the past. Calling Camarda an outlier is just a different way of stating this problem.
"It is likely that Artemis II will land safely" and "Artemis II is Not Safe to Fly" are both compatible with the probability of a disaster on reentry being 10%.
> In both Challenger and Columbia, nobody bothered to analyze the problem because they didn't think there was a problem.
Being pedantic, NASA management "ignored" engineers - because money.
That said, I 100% agree with you assuming:
> “We have full confidence in the Orion spacecraft and its heat shield, grounded in rigorous analysis and the work of exceptional engineers who followed the data throughout the process,” Isaacman said Thursday.
I only say assuming not that I don't believe Isaacman, but historically NASA managers have said publicly everything's fine when it wasn't and tried to throw the blame onto engineers.
With Challenger, engineers said no-go.
With Columbia, engineers had to explicitly state/sign "this is unsafe", which pushes the incentivisation the wrong direction.
So, I want to believe him, but historically it hasn't been so great to do so.
"It will be the second flight of the Space Launch System (SLS), the first crewed mission of the Orion spacecraft, and the first crewed mission beyond low Earth orbit since Apollo 17 in 1972."
such "second/first" were ok 60 years ago. Today the only reason for that is that the SLS isn't reusable while the cost is hyper-astronomical.
Today's tech complexity, engineering culture and overall managerial processes don't allow the first/second to succeed. Even the best - Space X - has got several failed launches back then for Falcon and now for Starship.
Someone please answer my obvious question. We sent successful missions to the moon sixty years ago. What heat shield material was used for the Apollo capsules, and why would we need something different now? Are the Artemis mission parameters totally different in a way that requires a new design? Or was Apollo incredibly dangerous and we got lucky they didn’t all fail catastrophically? The article mentions Orion is much heavier than the Apollo capsules, does that really require a totally novel heat shield that takes $billions to develop?
The Apollo command module used Avcoat, the same material as Orion. But there are two key differences:
1. The application method is different. Apollo applied it to a metal honeycomb structure with very small cells, while Orion uses blocks of the material. (NASA tried the honeycomb approach for Orion, but it was too labor-intensive).
2. Orion is much bigger and heavier than the Apollo command module. The informal consensus is that Apollo may have been at the upper size limit for using Avcoat.
Engineering is done in the context of constraints, cost is one constraint - and its a relatively conserved constraint. Saving labor in one area allows for more care in other areas. Especially given that labor is often not cost constrained, but skill constrained, which is less elastic.
This is a concerning read, I'm not quite sure what the driving motivation is for Artemis, but the following answered at least part of my question -
> That context is a moon program that has spent close to $100 billion and 25 years with nothing to show for itself, at an agency that has just experienced mass firings and been through a near-death experience with its science budget
> “Our test facilities can’t reach the combination of heat flux, pressure, shear stresses, etc., that an actual reentering spacecraft does. We’re always having to wait for the flight test to get the final certification that our system is good to go.”—Jeremy VanderKam, deputy manager for Orion’s heat shield, speaking in 2022
The Orion heat shield is sixteen feet across. NASA's test facilities can only test small material samples in these facilities, not capture how the entire heat shield will behave.
There were 19 successful unmanned Dragon 1 missions before Crew Dragon, and an unmanned Crew Dragon mission before the first crewed one (actually two missions, but one didn't reenter from orbit). The heat shield material and design was essentially the same and so there was a great deal of flight heritage.
In particular I don't think its physically possible to test Orion components in flight very many times. It relies on SLS which chews through 4 space-shuttle engines every time, which even with unlimited money I don't think you could acquire a large supply of very quickly.
By having a much higher launch cadence and then analyzing the flight hardware afterwards.
Also, they don't have anything human rated going beyond LEO. Coming back from the moon means you're going significantly faster and thus need a better heat shield
I am very not brave but I'd volunteer. The trip is far more awesome than anything I have planned for the rest of my life. And if the shield fails on reentry it would only hurt for a few seconds. So if the crew and the backups and their backups read this and have second thoughts, ping me.
That’s definitely not my point, what I meant was it’s not unreasonable for someone who’s older - maybe children have grown, at our nearing retirement, etc. - why not take a risk to fly to space?
But that was exactly the point I was responding to, no? If NASA was fine with skipping the astronauts, then they would just send it unmanned, not find a random volunteer.
especially not one that may chicken out ( "very not brave" ) and destroy the cabin from the inside out by any means necessary (bashing at walls, pissing in cracks, etc.)
Definitely concerned to hear but I’m hopeful that the core of nasa is intact. They’re some of the kindest and smartest people I’ve had the pleasure of meeting. They don’t joke around with lives on the line. I hope the best for everyone involved. I’ll be watching the launch of Artemis 2 and 3 with excitement and hope.
The only thing the author of this blog piece has to offer that’s new is his very strong personal intuition that the new design hasn’t been properly validated, without any engineering explanation about why the testing the performed won’t adequately simulate real world performance.
I’m fairly confident NASA doesn’t read Maciej’s blog. However I’m confident that many people there read the Google doc he linked to. I suggest you do too.
> The trouble is that the heat shield on Orion blows chunks. Not in some figurative, pejorative sense, but in the sense that when NASA flew this exact mission in 2022, large pieces of material blew out of Orion’s heat shield during re-entry, leaving divots. Large bolts embedded in the heat shield also partially eroded and melted through.
Fun wording. This isn't news, concerns have been raised about Artemis II saftey in the past 3+ years since Artemis I and before then as well.
This is actually what is thought to partially have caused the damage seen previously. The new trajectory is supposed to just have a single heating pulse instead of two.
Aerobraking causes heat cycles. Expanding and contracting a material that already has "not large, large chunks missing" doesn't seem very prudent. Even before the evidence of deterioration, I'm not sure the safety culture at NASA would reach for that any time soon when a single high-temp event would work.
What I don't get is why the heck are the astronauts willing to risk their lives on something they must know by now is so dangerous? Is it really better to risk death than to risk getting fired?
To be honest I don't know how close to non-fiction "The Right Stuff" (book or film) was but if you watch it you'd maybe gain an understanding for why astronauts do these things. At least that part is believable.
This degree of lifespan-maximization is something you might have but others don’t necessarily share. E.g. old people went to Fukushima to sort it out. “Was it really better to risk death than to risk getting fired?”
Neither of these are major risks compared to never being what you want to be.
Some people go to war for the thrill of it, others do base jumping, free solo climbing and whole lot of other activities that eventually kill many of them. It is in their genes.
The author seems to have a pretty extensive history of… strong disdain for Artemis II. While has mentioned concerns about the heat shield before it was in the context of a laundry list of complaints, and it was nowhere close to the top.
I’m not a rocket scientist, but then neither is the author.
> if a commercial crew capsule (SpaceX Dragon or Boeing Starliner) returned to Earth with the kind of damage seen on Orion, NASA would insist on a redesign and an unmanned test flight to validate it.
Did they demand an unmanned flight just to prove it worked? Or did they accept an entirely new design based on modeling and ground tests and then immediately flew it with crew on board?
Then again I'm not one of those people who roots for NASA to fail for some reason.
They had a heat shield on the capsule that failed testing, so they swapped out the interchangeable heat shield for one that passed testing.
There was no entirely new design, there was no new material science, it was the same heat shield that the previous crewed capsules have used without the manufacturing defect.
> SpaceX's next Crew Dragon mission (Crew-5) will fly with a different, updated heat shield structure after a new composite substrate failed acceptance testing
I don't know what "new" or "different" or "updated" or "structure" mean then anymore.
Great read and interesting article. Hard to believe that NASA would risk astronauts lives simply to save face, but that appears to be what's going to happen.
Riskier? Didn't they all die. Maybe if you ended up with 2 stranded shuttle crews, but correct me if I'm wrong, and I probably am, but couldn't the shuttle fly without any crew?
It couldn't, for a funny reason. Everything on a Shuttle flight could be automated except lowering the landing gear just before touchdown, which had to be done by hand from inside the cockpit.
There are rumors (that I've never been able to run down) that the astronaut corps insisted on this so the Shuttle could not be flown unmanned.
You can do a less risky thing and die or do a more risky thing and live. What happened doesn’t determine which thing is riskier just like I can call a 1 and roll dice and land it and you can call tails and flip a coin and not get it.
The outcome doesn’t determine the risk. I agree that this kind of office politics / face savings definitely is the cause of these two things.
You seem to be ignoring the "just to save face" part. I'd argue it would be a worse thing for our bar for how safe it should be to be raised significantly from when we had been in space as a species less than a decade to now that it's been 65 years.
Saturn 5 had a flawless record. The leftover space shuttle parts which SLS is cobbled together from, not so much. SRBs are inherently dangerous, theyre designed to quickly launch nukes from silos, not people. And Orion is just a typical modern Boeing project. So far its fallen at every hurdle right?
Saturn 5 came close to catastrophic failure at least once. It had partial failures. Its sort of perfect record is mostly down to luck and not launching very many times.
Of course, six decades later, we should be able to do a lot better.
Yeah, I thought it was Starliner on top. I dont know anything about Orion then.
SLS is very crappy and disappointing, its using shitty old space shuttle tech, + its ridiculously expensive in terms of payload to orbit, but it will probably work.
I didnt know, cus I just dont give a shit about this stupid project.
They’ve killed dozens during the shuttle program , or did you forget ? Also a number during Gemini, Mercury and Appollo. Terrible safety record , and 5x worse than Soyuz . Shuttle fatality rate was 1/10. Approaching Russian roulette odds
In total, a little over one dozen astronauts died on shuttle flights (14). No astronauts died during Gemini or Mercury. Three died in a test on Apollo 1. The shuttle failure rate was nowhere close to 1/10. In fact, it was 1/67 (2 failures out of 134 flights).
As someone who is actually (still) a fan of basic research, Artemis looks like a fun time for the 1% with a $100 billion dollar price tag, except that since it's only 4 astronauts and support staff, it's less than 1%. I opposed messing with NASA funding for a long time, but arguments referencing spin-off tech and so on wear thin. Spin-off occurring lately would/could only be captured by existing billionaires anyway, and without much benefit for society in general.
Humans in space are currently still a waste of time/money, largely just a big surrender to PR, space-selfies, the attention economy, and the general emphasis on "seem not be" you see elsewhere. Please just send robots, build a base, and let us know when we can put more than ~10 freaking people up there at one time. If that fails, then at least we'll have results in robotics research that can be applicable elsewhere on Earth right now as well as help us achieve the more grand ambitions later.
House is on fire, has been for a while, fuck business as usual. I honestly think all those smart people ought to be charged with things like using their operations research to improve government generally, or with larger-scale high tech job programs. If you don't want to let NASA big-brains try to fix healthcare, we could at least let them fix the DMV. Hell, let them keep their spin-offs too, so they actually want success, and have some part of their budget that won't disappear. Basic research and fundamental science is (still) something we need, but we need to be far more strategic about it.
Food for thought: The way things are going, we can definitely look forward to a NASA that's completely transformed into an informal, but publicly funded, research/telemetry arm for billionaire asteroid-mining operations, and thus more of the "public risk, private-profits" thing while we pad margins for people who are doing fine without the help. OTOH, if NASA is running asteroid mining businesses at huge profits, then they can do whatever they want with squishy volunteers as a sideshow, and maybe we'll have enough cash left over to fund basic income.
> Moon-to-Mars Deputy Administrator Amit Kshatriya said: “it was very small localized areas. Interestingly, it would be much easier for us to analyze if we had larger chunks and it was more defined”. A Lockheed Martin representative on the same call added that "there was a healthy margin remaining of that virgin Avcoat. So it wasn’t like there were large, large chunks.”
Followed by:
> The Avcoat material is not designed to come out in chunks. It is supposed to char and flake off smoothly, maintaining the overall contours of the heat shield.
This is echoes both Shuttle incidents. Challenger: no gasses were supposed to make it past the o-rings no matter what, but when it became clear that gasses were escaping and the o-rings were being damaged, there was a push to suggest that it's an acceptable level.
There was a similar situation with heat shield damage and Columbia.
In both cases some models were used to justify the decision, with wild extrapolations and fundamentally, a design that wasn't expected to fail in that mode /at all/.
I know the points that astronauts make about the importance of manned space exploration, but I agree with this author that it seems to make sense to run this as an unmanned mission, and probably test the new heat shield which will replace the Artemis II design in an unmanned re-entry as well.
At this point in time, manned space exploration should come out of our entertainment budget. The same budget we use for football or olympic games.
https://arstechnica.com/space/2026/01/nasa-chief-reviews-ori...
Camarda is an outlier. The engineers at NASA believe it is safe. The astronauts believe it is safe. Former astronaut Danny Olivas was initially skeptical of the heat shield but came around.
And note that the OP believes it is likely (maybe very likely) that the heat shield will work fine. It's hard for me to reconcile "It is likely that Artemis II will land safely" with "Artemis II is Not Safe to Fly", unless maybe getting clicks is involved.
Regardless, this is not a Challenger or Columbia situation. In both Challenger and Columbia, nobody bothered to analyze the problem because they didn't think there was a problem. That's the difference, in my opinion. NASA is taking this seriously and has analyzed the problem deeply.
They are not YOLO'ing this mission, and it's somewhat insulting that people think they are.
The foam shedding/impact problem was heavily analyzed throughout the Shuttle program, and recognized as a significant risk. Read the CAIB report for a good history.
That report also describes the groupthink dynamic at NASA that made skeptical engineers "come around" for the good of the program in the past. Calling Camarda an outlier is just a different way of stating this problem.
Being pedantic, NASA management "ignored" engineers - because money.
That said, I 100% agree with you assuming:
> “We have full confidence in the Orion spacecraft and its heat shield, grounded in rigorous analysis and the work of exceptional engineers who followed the data throughout the process,” Isaacman said Thursday.
I only say assuming not that I don't believe Isaacman, but historically NASA managers have said publicly everything's fine when it wasn't and tried to throw the blame onto engineers.
With Challenger, engineers said no-go.
With Columbia, engineers had to explicitly state/sign "this is unsafe", which pushes the incentivisation the wrong direction.
So, I want to believe him, but historically it hasn't been so great to do so.
it doesn't matter.
https://en.wikipedia.org/wiki/Artemis_II
"It will be the second flight of the Space Launch System (SLS), the first crewed mission of the Orion spacecraft, and the first crewed mission beyond low Earth orbit since Apollo 17 in 1972."
such "second/first" were ok 60 years ago. Today the only reason for that is that the SLS isn't reusable while the cost is hyper-astronomical.
Today's tech complexity, engineering culture and overall managerial processes don't allow the first/second to succeed. Even the best - Space X - has got several failed launches back then for Falcon and now for Starship.
1. The application method is different. Apollo applied it to a metal honeycomb structure with very small cells, while Orion uses blocks of the material. (NASA tried the honeycomb approach for Orion, but it was too labor-intensive).
2. Orion is much bigger and heavier than the Apollo command module. The informal consensus is that Apollo may have been at the upper size limit for using Avcoat.
So cost cutting, as always.
> That context is a moon program that has spent close to $100 billion and 25 years with nothing to show for itself, at an agency that has just experienced mass firings and been through a near-death experience with its science budget
This is a strange claim, considering NASA used to have 2 facilities that were capable of this - one at Johnson and one at Ames. They were consolidated (https://ntrs.nasa.gov/api/citations/20160001258/downloads/20...) but it seems like the Arc Jet Complex at Ames is still operational https://www.nasa.gov/ames/arcjet-complex/
Also, they don't have anything human rated going beyond LEO. Coming back from the moon means you're going significantly faster and thus need a better heat shield
>> Artemis II could fly just as easily without astronauts on board
Anyone know if there's a detailed response from NASA to the article?
The only thing the author of this blog piece has to offer that’s new is his very strong personal intuition that the new design hasn’t been properly validated, without any engineering explanation about why the testing the performed won’t adequately simulate real world performance.
"countdown clock started ticking down" "to a targeted launch time of 6:24 p.m. on Wednesday, April 1."
> NASA’s initial instinct was to cover up the problem.
to at least warrant a link.
Fun wording. This isn't news, concerns have been raised about Artemis II saftey in the past 3+ years since Artemis I and before then as well.
Is Orion’s heat shield really safe? New NASA chief conducts final review on eve of flight. https://arstechnica.com/space/2026/01/nasa-chief-reviews-ori...
Neither of these are major risks compared to never being what you want to be.
I want you to repeat those words as you melt away re-entering the atmosphere.
I’m not a rocket scientist, but then neither is the author.
Are you sure about that?
https://spaceflightnow.com/2022/05/24/spacex-swapping-heat-s...
Then again I'm not one of those people who roots for NASA to fail for some reason.
They had a heat shield on the capsule that failed testing, so they swapped out the interchangeable heat shield for one that passed testing.
There was no entirely new design, there was no new material science, it was the same heat shield that the previous crewed capsules have used without the manufacturing defect.
I don't know what "new" or "different" or "updated" or "structure" mean then anymore.
There are rumors (that I've never been able to run down) that the astronaut corps insisted on this so the Shuttle could not be flown unmanned.
The outcome doesn’t determine the risk. I agree that this kind of office politics / face savings definitely is the cause of these two things.
Of course, six decades later, we should be able to do a lot better.
I didnt know, cus I just dont give a shit about this stupid project.
Columbia and Challenger crew totaled 14, who else are you referring to?
Humans in space are currently still a waste of time/money, largely just a big surrender to PR, space-selfies, the attention economy, and the general emphasis on "seem not be" you see elsewhere. Please just send robots, build a base, and let us know when we can put more than ~10 freaking people up there at one time. If that fails, then at least we'll have results in robotics research that can be applicable elsewhere on Earth right now as well as help us achieve the more grand ambitions later.
House is on fire, has been for a while, fuck business as usual. I honestly think all those smart people ought to be charged with things like using their operations research to improve government generally, or with larger-scale high tech job programs. If you don't want to let NASA big-brains try to fix healthcare, we could at least let them fix the DMV. Hell, let them keep their spin-offs too, so they actually want success, and have some part of their budget that won't disappear. Basic research and fundamental science is (still) something we need, but we need to be far more strategic about it.
Food for thought: The way things are going, we can definitely look forward to a NASA that's completely transformed into an informal, but publicly funded, research/telemetry arm for billionaire asteroid-mining operations, and thus more of the "public risk, private-profits" thing while we pad margins for people who are doing fine without the help. OTOH, if NASA is running asteroid mining businesses at huge profits, then they can do whatever they want with squishy volunteers as a sideshow, and maybe we'll have enough cash left over to fund basic income.