https://x.com/elonmusk/status/1984868748378157312
They're already having a negative, contaminating effect on our upper atmosphere
Sending up bigger ones, and more (today there's some 8,800, but they target 30k), sounds ill-advised.
1: https://www.fastcompany.com/91419515/starlink-satellites-are... 2: https://www.science.org/content/article/burned-satellites-ar...
Am I missing something? Feels like an extremely strong indicator that we're in some level of AI bubble because it just doesn't make any sense at all.
I'm surprised that Google has drunken the "Datacenters IN SPACE!!!1!!" kool-aid. Honestly I expected more.
It's so easy to poke a hole in these systems that it's comical. Answer just one question: How/why is this better than an enormous solar-powered datacenter in someplace like the middle of the Mojave Desert?
I think it's a good idea, actually.
A giant space station?
> no need for security
There will be if launch costs get low enough to make any of this feasible.
> no premises
Again… the space station?
> no water
That makes things harder, not easier.
>There will be if launch costs get low enough to make any of this feasible.
I don't know what you mean by that.
Fundamentally, it is, just in the form of a swarm. With added challenges!
> I don't know what you mean by that.
If you can get to space cheaply enough for an orbital AI datacenter to make financial sense, so can your security threats.
Right, in the same sense that existing Starlink constellation is a Death Star.
This paper does not describe a giant space station. It describes a couple dozen of satellites in a formation, using gravity and optics to get extra bandwidth for inter-satellite links. The example they gave uses 81 satellites, which is a number made trivial by Starlink (it's also in the blog release itself, so no "not clicking through to the paper" excuses here!).
(In a gist, the paper seems to be describing a small constellation as useful compute unit that can be scaled, indefinitely - basically replicating the scaling design used in terrestrial ML data centers.)
I have my doubts that it's with it with current or near future launch costs. But at least it's more realistic than putting solar arrays in orbit and beaming the power down
It's probably not why they're interested in it, but I'd like to imagine someone with a vision for the next couple decades realized that their company already has data centers and powering them as their core competency, and all they're missing is some space experience...
It gets very exciting if you don't have enough.
> Nothing to obsess about.
It's one of the primary reasons these "AI datacenters… in space!" projects are goofy.
In fact everything in this paper is already solved by SpaceX except GPU cooling.
It's not absent - it's covered in the paper, which this blog release summarizes. There's a link to the paper itself in the side bar.
> In fact everything in this paper is already solved by SpaceX except GPU cooling.
Cooling is already solved by SpaceX too, since this paper basically starts with the idea of swapping out whatever payload is on Starlink with power-equivalent in TPUs, and then goes from there.
ceejayoz•2h ago
Sure. Now do cooling. That this isn't in the "key challenges" section makes this pretty non-serious.
A surprising amount of the ISS is dedicated to this, and they aren't running a GPU farm. https://en.wikipedia.org/wiki/External_Active_Thermal_Contro...
boutell•2h ago
TeMPOraL•56m ago
This is not the 1960s. Today, if you have an idea for doing something in space, you can start by scoping out the details of your mission plan and payload requirements, and then see if you can solve it with parts off a catalogue.
(Of course there's million issues that will crop up when actually designing and building the spacecraft, but that's too low level for this kind of paper, which just notes that (the authors believe) the platform requirements fall close enough to existing systems to not be worth belaboring.)
xnx•2h ago
eminence32•2h ago
stronglikedan•2h ago
abtinf•1h ago
TeMPOraL•1h ago
TeMPOraL•1h ago
More seriously though, the paper itself touches on cooling and radiators. Not much, but that's reasonable - cooling isn't rocket science :), it's a solved problem. Talking about it here makes as much sense as taking about basic attitude control. Cooling the satellite and pointing it in the right direction are solved problems. They're important to detail in full system design, but not interesting enough for a paper that's about "data centers, but in space!".
ceejayoz•1h ago
It's solved on Earth because we have relatively easy (and relatively scalable) ways of getting rid of it - ventilation and water.
TeMPOraL•1h ago
ceejayoz•1h ago
Sure, in the same sense that I could build a bridge from Australia to Los Angeles with "no new tech". All I have to do is find enough dirt!
TeMPOraL•1h ago
We're past the point of every satellite being a custom R&D job resulting in an entirely bespoke design. We're even moving past the point where you need to haggle about every gram; launch costs have dropped a lot, giving more options to trade mass against other parameters, like more effective heat rejection :).
But I think the first and most important point for this entire discussion thread is: there is a paper - an actual PDF - linked in the article, in a sidebar to the right, which seemingly nobody read. It would be useful to do that.
ceejayoz•1h ago
Now ask them to do the Australia / Los Angeles one.
"lol no"
The where and the scale matter.
TeMPOraL•1h ago
Scale: Lots of small satellites.
I.e. done to death and boring. Number of spacecraft does not affect the heat management of individual spacecraft.
Much like number of bridges you build around the world does not directly affect the amount of traffic on any individual one.
ceejayoz•1h ago
Challenging!
> Scale: Lots of small satellites.
So we're getting cheaper by ditching economies of scale?
There's a reason datacenters are ever-larger giant warehouses.
> Much like number of bridges you build around the world does not directly affect the amount of traffic on any individual one.
But there are places you don't build bridges. Because it's impractical.
TeMPOraL•1h ago
estimator7292•1h ago
We do not have a solution for getting rid of megawatts or gigawatts of heat in space.
What the sibling comment is pointing out is that you cannot simply scale up any and every technology to any problem scale. If you want to get rid of megawatts of heat with our current technology, you need to ship up several tons of radiators and then build massive kilometer-scale radiation panels. The only way to dump heat in space is to let a hot object radiate infrared light into the void. This is an incredibly slow and inefficient process, which is directly controlled by the surface area of your radiator.
The amount of radiators you need for a scheme like this is entirely out of the question.
TeMPOraL•23m ago
1. Take existing satellite designs like Starlink, which obviously manage to utilize certain amount of power successfully, meaning they solved both collection and heat rejection.
2. Pick one, swap out its payload for however many TPUs it can power instead. Since TPUs aren't an energy source, the solar/thermal calculation does not change. Let X be the compute this gives you.
3. Observe that thermal design of a satellite is independent from whether you launch 1 or 10000 of them. Per point 2, thermals for one satellite are already solved, therefore this problem is boring and not worth further mention.
4. Play with some wacky ideas about formations to improve parameters like bandwidth, while considering payload-specific issues like radiation hardening, NONE OF WHICH HAVE ANY IMPACT ON THERMALS[0]. This is the interesting part. Publish it as a paper.
5. Have someone make a press release. A common mistake.
6. Watch everyone get hung up on the press release and not bother clicking through to the actual paper.
--
[0] - Well, some do. Note that fact in the paper.
paulsutter•43m ago
From https://x.com/elonmusk/status/1984249048107508061:
"Simply scaling up Starlink V3 satellites, which have high speed laser links would work. SpaceX will be doing this."
From https://x.com/elonmusk/status/1984868748378157312:
"Starship could deliver 100GW/year to high Earth orbit within 4 to 5 years if we can solve the other parts of the equation. 100TW/year is possible from a lunar base producing solar-powered AI satellites locally and accelerating them to escape velocity with a mass driver."
ceejayoz•29m ago
I'm sure they'll be ready right after the androids and the robotaxi and the autonomous LA-NYC summoning.
> Starlink v3 already has a 60M length solar array, so they're already solving dissipation for that size.
Starlink v3 doesn't exist yet. They're renders at this point. Full-sized v2s haven't even flown yet, just mass simulators.
https://en.wikipedia.org/wiki/Starlink#Satellite_revisions
mncharity•23m ago
GPT says 1000 W at 50 C takes about 3 m^2 to radiate (edge on to Earth and Sun), and generating that 1000 W takes about... 3 m^2 of solar panel. The panel needs its backside radiator clear to keep itself coolish (~100 C), so it does need to be a separate surface. Spreading a 1000 W point source across a 3 m^2 tile (or half that if two-sided?) is perhaps not scary, even with weight constraints?
Hmm, from an order-of-magnitude perspective, it looks like an (L shaped) Starlink v2 sat has 100 m^2 of panel, low 10 kW draw, and a low 100 m^2 body area. And there are 10 k of them. So want something bigger. A 100 x 100 m sheet might get you 10 sats per 100,000 GPU data center.
Regards ISS, ISS has its big self, basking in the sunlight, needing to be cooled. Versus "the only thing sun-lit is panel".