How NASA built Artemis II’s fault-tolerant computer • Hacker News Board

Re: How NASA built Artemis II’s fault-tolerant computer

#131

Post by ForHackernews » Fri, Apr 10, 2026, 9:03 AM UTC

nickff wrote: post #57

dyauspitr wrote: post #54

Earlier quoted context omitted.

Agile is not meant to make solid, robust products. It’s so you can make product fragments/iterations quickly, with okay quality and out to the customer asap to maximize profits.

“Agile” doesn’t mean that you release the first iteration, it’s just a methodology that emphasizes short iteration loops. You can definitely develop reliable real-time systems with Agile.

SCRUM methodology absolutely prioritizes a "Potentially Shippable Product Increment" as the output of every sprint.

Re: How NASA built Artemis II’s fault-tolerant computer

#132

Post by mcdeltat » Fri, Apr 10, 2026, 9:16 AM UTC

weli wrote: post #130

therobots927 wrote: post #74

Earlier quoted context omitted.

Contrary to propaganda from the likes of Ludwig von Mises, the free market is not some kind of optimal solution to all of our problems. And it certainly does not produce excellent software.

Mises never claimed that the free market produced the most optimal solutions at a given moment. In fact Mises explicitly stated many times that the free market does indeed incur in semi-frequent self-corrections, speculations and manipulations by the agents. What Mises proposition was - in essence - is that an autonomous market with enough agents participating in it will reach an optimal Nash equilibrium where both o…

> optimal Nash equilibrium where both offer and demand are balanced

This roughly translates to "optimal utopian society which cannot be criticised in any way" right? Right??

Re: How NASA built Artemis II’s fault-tolerant computer

#133

Post by brodock » Fri, Apr 10, 2026, 9:21 AM UTC

nairboon wrote: post #125

therobots927 wrote: post #74

Earlier quoted context omitted.

Contrary to propaganda from the likes of Ludwig von Mises, the free market is not some kind of optimal solution to all of our problems. And it certainly does not produce excellent software.

Propaganda is quite a strong term to describe the works of an economist. If one wants to debate the ideas of von Mises, it'd be useful to consider the Zeitgeist at that time. Von Mises preferred free markets in contrast to the planned economy of the communists. Partly because the latter has difficulties in proper resource allocation and pricing. Note that this was decades before we had working digital computers and d…

Governament contracts are very restricted behind layers of certifications and authorizations.

For example, you can't freely produce missiles and have it in wallmart where "the governament" purchase at shelf price.

Re: How NASA built Artemis II’s fault-tolerant computer

#134

Post by gambiting » Fri, Apr 10, 2026, 9:24 AM UTC

BitsAndObjects wrote: post #127

gambiting wrote: post #118

So honest and perhaps a bit stupid question. Astronauts have actual phones with them - iPhones 17 I think? And a regular Thinkpad that they use to upload photos from the cameras. How does all of that equipment work fine with all the cosmic radiation floating about? With the iPhone's CPU in particular, shouldn't random bit flips be causing constant crashes due to errors? Or is it simply that these errors happen but no…

They’re not mission-critical equipment. If they fail, nobody dies. They’re not radiation hardened, so given enough time, they’d be expected to fail. Rebooting them might clear the issue or it might not (soft vs hard faults). Also impossible to predict when a failure would happen, but NASA, ESA and others have data somewhere that makes them believe the risk is high enough that mission critical systems need this level…

>>They’re not mission-critical equipment. If they fail, nobody dies.

Yes, for sure, but that's not my question - it's not a "why is this allowed" but "why isn't this causing more visible problems with the iphones themselves".

Like, do they need constant rebooting? Does this cause any noticable problems with their operation? Realistically, when would you expect a consumer grade phone to fail in these conditions?

Re: How NASA built Artemis II’s fault-tolerant computer

#135

Post by weli » Fri, Apr 10, 2026, 9:33 AM UTC

mcdeltat wrote: post #132

weli wrote: post #130

Earlier quoted context omitted.

Mises never claimed that the free market produced the most optimal solutions at a given moment. In fact Mises explicitly stated many times that the free market does indeed incur in semi-frequent self-corrections, speculations and manipulations by the agents. What Mises proposition was - in essence - is that an autonomous market with enough agents participating in it will reach an optimal Nash equilibrium where both o…

> optimal Nash equilibrium where both offer and demand are balanced This roughly translates to "optimal utopian society which cannot be criticised in any way" right? Right??

I don't know if you are being sarcastic. But no, it's not an "utopia" by any means and the free market still has many pitfalls and problems that I described. However, is the best system we have to coordinate the production, distribution and purchasing of services and goods on a mass scale.

Re: How NASA built Artemis II’s fault-tolerant computer

#136

Post by kev009 » Fri, Apr 10, 2026, 9:35 AM UTC

Some people are claiming it's the good old RAD750 variant. Is there anything that talks about the actual computer architecture? The linked article is desperately void of technical details.

Re: How NASA built Artemis II’s fault-tolerant computer

#137

Post by vintermann » Fri, Apr 10, 2026, 9:37 AM UTC

dyauspitr wrote: post #54

dmk wrote: post #3

The quote from the CMU guy about modern Agile and DevOps approaches challenging architectural discipline is a nice way of saying most of us have completely forgotten how to build deterministic systems. Time-triggered Ethernet with strict frame scheduling feels like it's from a parallel universe compared to how we ship software now.

Agile is not meant to make solid, robust products. It’s so you can make product fragments/iterations quickly, with okay quality and out to the customer asap to maximize profits.

The generous way of seeing it is that you don't know what the customer wants, and the customer doesn't know all that well what they want either, and certainly not how to express it to you. So you try something, and improve it from there.

But for aerospace, the customer probably knows pretty well what they want.

Re: How NASA built Artemis II’s fault-tolerant computer

#138

Post by pjc50 » Fri, Apr 10, 2026, 9:40 AM UTC

nairboon wrote: post #125

therobots927 wrote: post #74

Earlier quoted context omitted.

Contrary to propaganda from the likes of Ludwig von Mises, the free market is not some kind of optimal solution to all of our problems. And it certainly does not produce excellent software.

Propaganda is quite a strong term to describe the works of an economist. If one wants to debate the ideas of von Mises, it'd be useful to consider the Zeitgeist at that time. Von Mises preferred free markets in contrast to the planned economy of the communists. Partly because the latter has difficulties in proper resource allocation and pricing. Note that this was decades before we had working digital computers and d…

> The government contractors (private enterprises) are usually tasked with building stuff

Ah yes, situation where the government makes a plan and then hands it to the one (1) qualified defense contractor whose facilities are build in swing states to benefit specific congressional campaigns is completely different from central planning.

Re: How NASA built Artemis II’s fault-tolerant computer

#139

Post by [deleted] » Fri, Apr 10, 2026, 9:40 AM UTC

dmk wrote: post #3

The quote from the CMU guy about modern Agile and DevOps approaches challenging architectural discipline is a nice way of saying most of us have completely forgotten how to build deterministic systems. Time-triggered Ethernet with strict frame scheduling feels like it's from a parallel universe compared to how we ship software now.

[deleted]

Re: How NASA built Artemis II’s fault-tolerant computer

#140

Post by 21asdffdsa12 » Fri, Apr 10, 2026, 9:45 AM UTC

ggm wrote: post #105

dmk wrote: post #3

The quote from the CMU guy about modern Agile and DevOps approaches challenging architectural discipline is a nice way of saying most of us have completely forgotten how to build deterministic systems. Time-triggered Ethernet with strict frame scheduling feels like it's from a parallel universe compared to how we ship software now.

Time triggered Ethernet is part of aircraft certified data bus and has a deep, decades long history. I believe INRIA did work on this, feeding Airbus maybe. It makes perfect sense when you can design for it. An aircraft is a bounded problem space of inputs and outputs which can have deterministic required minima and then you can build for it, and hopefully even have headroom for extras. Ethernet is such a misnomer fo…

Aircraft also have software and components, that form a "working" proclaimed eco-system in lockstep- a baseline. This is why there are paper "additions" on bug discovery until the bug is patched and the whole ecosystem of devices is lifted to the next "baseline".