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Google’s Project Suncatcher to put ML infrastructure in space

233 points · 553 comments · xnx

zactato · 1790267254 · focus · HN ↗
How are they solving the heat dissipation issues?
1. GMoromisato · 1790270501 · focus · HN ↗
  Please stop with this argument. This is one of the easiest problems to solve. Heat dissipation requires a radiator, which is just a dumb hunk of metal. All you need is a cheap way to launch mass to orbit, which is exactly what SpaceX (and Chinese companies) are doing.
  The only valid argument against data centers in space is the economic cost. If the per megatoken price for space datacenters is higher than terrestrial, then this won't work.
  But the price for terrestrial datacenters keeps going up and technology keeps dropping the price of space-based.
  1. 0cf8612b2e1e · 1790272676 · focus · HN ↗
    That is not a fake argument, but real physics. Yes, you can design out X kw can be dissipated by this much radiators, but that adds an enormous quantity of mass, more than the solar panels that feed it.
    If you are trying to generate a profit, every extra kg puts you further in the red. It still costs over $1000/kg of mass to get into orbit.
    GMoromisato · 1790275041 · focus · HN ↗
    So is it a physics problem or an economic problem? Sounds to me like you are acknowledging that it is just an economic problem. If it cost $1/kg to get to orbit then this wouldn't be a problem, right? Just make a bigger radiator.
    But if it's an economic argument, then you need to do the actual math. How big is the radiator? How low could the price to orbit go? How much can you charge per million tokens in 2030?
    The reason this is a fake argument is because the validity depends on the math, and nobody advancing the "you can't cool stuff in space" argument is actually doing the math.
    cyberax · 1790282091 · focus · HN ↗
    It's a fundamental physics problem. You need to have huge radiating surfaces.
    A 1GW datacenter with chips operating at 100C (which is probably doable) will need a radiator that has a surface of one square _kilometer_, and this is with all the favorable assumptions. Realistically you'll need about 2x of that.
    If you want your DCs to be on a 1000km orbit (for reasonable ping times), you'll be able to _resolve_ these satellites with a naked eye!
    Sorry. But this idea is fundamentally unworkable.
    GMoromisato · 1790282643 · focus · HN ↗
    The current plan is for 250 kW peak with 160 m^2 radiators. It will weigh about 4 tons so you can pack 25 on one flight of Starship.
    Deploy 4,000 and you're at 1 GW. That's 160 launches.
    BTW: SpaceX has already manufactured and launched 10,000 Starlink satellites and Falcon 9 launches about 150 times per year. None of this seems unworkable.
    cyberax · 1790285003 · focus · HN ↗
    Can we solve the fertilizer price problem by hauling it with airplanes? Yes, we can! It's easy, just load the potash fertilizer into an airplane and unload it directly into the traincars. I even designed a neat conveyor belt system to speed up unloading!
    Look at the numbers. 1kW of nuclear power capacity on Earth is around $2000, and that's 24/7 guaranteed power. So a 250kW cluster needs $500000 to cover its power demand with near 100% reliability and with some ongoing cost.
    And if we're OK with some interruptions, then we can use solar+wind at around $100000 and with essentially no ongoing cost. If we assume the absolutely best projected launch cost of $100 per kg (vs the current one of ~$800), that's just 1 ton of material in space!
    So you're off by 2-3 orders of magnitude in cost. And this kind of "it's unprofitable" is actually a fundamental issue.
    GMoromisato · 1790293813 · focus · HN ↗
    Okay, so you admit it is possible. Cooling is not the problem. We're making progress.
    Now your argument is that it's unprofitable. Here's the calculator: <a href="https://andrewmccalip.com/space-datacenters" rel="nofollow">https://andrewmccalip.com/space-datacenters
    Specifically, if SpaceX can get the price of a satellite down to $8 per watt (about $2 million USD) then it will compete with terrestrial.
    I just don't understand how you can be so certain that they can't do that. I'm not certain that they can, but being certain that it's impossible seems completely evidence-free.
    cyberax · 1790294863 · focus · HN ↗
    This calcualtor is bullshit (inflated terrestrial costs and underflated orbital costs). It doesn't pass the basic sniff test: $15B for 1GW of terrestrial power is more than enough to build AN ENTIRE 3GWe NUCLEAR POWER PLANT. From scratch. With 75 years of expected life.
    So no, the calculations show that space is NOT feasible unless you want to do that for nefarious reasons: evading regulations, using AI for criminal enterprises, military use, that sort of thing.
    Only these applications have the profit margin that even comes close to justifying it.

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