Item — HN Reader

They do and you’re the one spreading misinformation… the amount of energy you need to radiate for inference GPUs is enormous compared to any computer currently used in space. Energy dissipation by radiating is literally the least effective method and would require insanely large radiators just to be effective on paper. You also need to mitigate bit flips, meaning you throw away around 2/3 of your compute capacity.

And that’s just the most basic things, before taking in account ALL the other problems you face doing compute in space someone with expertise in the domain could mention.

Datacenters in space is a grift that won’t happen in any meaningful capacity and can be debunked by a 15y old who followed their physics courses

1 comments

You've listed:

1. Radiating heat needs large radiators 2. Bit flips require extra compute capacity

Neither of those violate the laws of physics. As I said, they may not work economically, but that depends on a large number of unknowns, including the cost per ton to orbit and the cost per GW of new power capacity on Earth in 2030. If you have a time machine and know those numbers, then can I please borrow your time machine?

Moreover, when you say, "ALL the other problems ... someone with expertise in the domain could mention," you're saying either:

A) SpaceX engineers do not have expertise in this domain. B) SpaceX engineers are hiding all the problems that they know about.

B is basically a conspiracy theory. It is one YouTube video away from saying the moon landing was a hoax.

A is just delusional.

> Neither of those violate the laws of physics. As I said, they may not work economically, but that depends on a large number of unknowns, including the cost per ton to orbit and the cost per GW of new power capacity on Earth in 2030. If you have a time machine and know those numbers, then can I please borrow your time machine?

Alphabet researchers have estimated future launch costs based on learning curves; they estimate that after Starship has launched 370,000 tons to LEO, they will have figured out how to reduce launch costs by enough to make space data centres viable.

They optimistically suggested this might take ten years.

Given the rate of development of Starship as a launch system, I suspect that Musk will reach federal pension age before this is viable.

Or potentially:

C) SpaceX engineers enjoy their cushy salary funded by a guy who won't take "that doesn't make sense" for an answer to work on rockets and neat technology, even if it may never really work out.

Do you know anyone that works at SpaceX? They get paid well, yes, but my friends who work there say they work you really hard. The bet that's being made is that there will be advancements in materials science that make data centers in space viable. If you hypothesize that there's a way to cool things down in space if you just had the right material to do it, it makes sense. Starlink satellites are already compute plus solar panels. Just scale it up! Or course "just" is doing a lot of work here, but that's the theory.

> Starlink satellites are already compute plus solar panels. Just scale it up!

Starlink satellites use probably less than 1/100th the power budget of even these earlier supposed plans. They don't use much power at all in comparison. They're also big flat pancake for their body, as they want to have a good bit of area for their antenna array. So the other side can just focus on cooling very close to the actual compute parts. It's a radically different set of engineering requirements.

For something line the AI1, you're looking at a few million in launch costs for the mass of the cooling system alone and that's assuming they get Starship flying around their projected costs. What's the install cost per rack or cooling equipment on the ground? Even say I'm overshooting it 100%, those numbers still don't sound very good!

That's a different conspiracy theory, for which there is also no evidence.

So between the giant radiator per GPU and the diminished compute capacity, how much mass are we shooting up exactly? This just seems utterly infeasible.

You're missing C) SpaceX engineers know it's a bad idea, but can't say anything because it's the tyrant manchild's latest obsession, technology constraints be damned.

Remember the vision-only FSD? How's that coming along?

> because it's the tyrant manchild's latest obsession, technology constraints be damned.

Imho, there's only one reason that justifies Musk's space-based compute obsession: sovereignty.

Specifically, avoiding terrestrial country's.

This isn't about AI in space (though I'm sure dumb investors love that), it's about uncensorable Twitter in space, beamed down to Starlink terminals.

Which would be one of the few things you'd care about, if you were one of the richest people on the planet... but still subject to those damned nations and their meddling laws.

That's exactly it. Musk sees space as extraterritorial, which in the true sense of the word of course it absolutely is. But all those bits have to go to ground somewhere. As long as that somewhere is friendly no problem. That can change.

If Elon wants to offer space-twitter, he still needs to abide by the rules of the country he is offering the service to.

Unless he's offering it to the aliens orbiting his magical lawless space data centers.

Does he?

Short of countrywide ku-band jamming and/or drone-based RDF at scale, what's the country going to do?

It was one thing when you needed a C-band dish to receive, but much harder to deal with a 1-2 ft dish.

They could, but this would be unnecessary.

I suspect that simply blocking payments from locals to Musk may be enough, considering how Musk reacted when advertisers voted with their wallets to leave X.

But nations have other tools, as Brazil showed when a judge ordered a freeze on Starlink assets because X didn't have reachable assets within Brazil to be frozen.

They could shoot down those data centers for example.

Unreasonably expensive for pLEO volumes (same problem/advantage militaries are looking at) + collateral damage to other nations satellites

The only nations who would realistically have that as an option would have a robust scaled ASAT capability (maybe US and China) but no pLEO satellites (rules out US and China).

Yeah, I think Musk loves the idea of sticking his CSAM generators in space, where he thinks they will be beyond the reach of terrestrial laws and morals.