Data centers in space makes no sense • Hacker News Board

Re: Data centers in space makes no sense

#381

Post by jimt1234 » Wed, Feb 04, 2026, 2:53 AM UTC

beloch wrote: post #115

I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…

> It makes far more sense to build data centers in the arctic.

Please, no!

Re: Data centers in space makes no sense

#382

Post by JackYoustra » Wed, Feb 04, 2026, 2:53 AM UTC

Data centers in space make sense because its nigh impossible to build things terrestrially. NIMBYism is so out of control the largest solar array in the US in the middle of the mojave got cancelled because it would interfere with the view.

"Just change the law" ok sure we'll get right on it.

Re: Data centers in space makes no sense

#383

Post by phendrenad2 » Wed, Feb 04, 2026, 2:56 AM UTC

beloch wrote: post #115

I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…

I think people underestimate how quickly heat radiates to space. A rock in orbit around Earth will experience 250F/125C on the side facing the Sun, and -173C/-280F on the other side. The ability to rotate an insulating shield toward the sun means you're always radiating.

Re: Data centers in space makes no sense

#384

Post by aunty_helen » Wed, Feb 04, 2026, 2:59 AM UTC

stackghost wrote: post #354

aunty_helen wrote: post #127

Earlier quoted context omitted.

The equation has a ^4 to the temperature. If you raise the temperature of your radiator by ~50 degrees you double its emission capacity. This is well within the range of specialised phase change compressors, aka fancy air conditioning pumps. Next up in the equation is surface emissivity which we’ve got a lot of experience in the automotive sector. And finally surface area, once again, getting quite good here with nan…

Even if you create a material with surface emissivity of 1.0: - let's say 8x 800W GPUs and neglect the CPU, that's 6400W - let's further assume the PSU is 100% efficient - let's also assume that you allow the server hardware to run at 77 degrees C, or 350K, which is already pretty hot for modern datacenter chips. Your radiator would need to dissipate those 6400W, requiring it to be almost 8 square meters in size. Tha…

Hence the fancy air conditioning pumps

Re: Data centers in space makes no sense

#385

Post by anywhichway » Wed, Feb 04, 2026, 3:02 AM UTC

b00ty4breakfast wrote: post #126

They're gonna propose something dumb like ejecting coolant out into space as a disposable heatsink and then they're gonna spend a bunch of money trying to build a proof-of-concept but it will never go anywhere because it's really some kinda money laundering scheme or whatever the Hyperloop nonsense was.

Musk said in his autobiography he announced the hyperloop plan without any intention of doing it to distract from the California high speed rail plans.

Re: Data centers in space makes no sense

#386

Post by rpcope1 » Wed, Feb 04, 2026, 3:02 AM UTC

beloch wrote: post #115

I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…

I think it's possibly more informative to look at what happened with SolarCity and Tesla and contemplate if there's not a similar dynamic here.

Re: Data centers in space makes no sense

#387

Post by perfmode » Wed, Feb 04, 2026, 3:03 AM UTC

Current analysis shows space-based compute costs roughly 3x more per watt than terrestrial equivalents, requiring launch costs to fall below $200/kg before achieving economic parity—a threshold unlikely before the mid-2030s even with Starship’s full reusability.

While technically not impossible, the space data center vision appears primarily designed to support SpaceX’s anticipated mid-2026 IPO and justify a $1.5 trillion valuation rather than solve near-term compute constraints.

Re: Data centers in space makes no sense

#388

Post by [deleted] » Wed, Feb 04, 2026, 3:04 AM UTC

beloch wrote: post #115

I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…

[deleted]

Re: Data centers in space makes no sense

#389

Post by adgjlsfhk1 » Wed, Feb 04, 2026, 3:05 AM UTC

gpt5 wrote: post #235

lancewiggs wrote: post #177

Earlier quoted context omitted.

It's exiting the 5th best social network and the 10th (or worse) best AI company and selling them to a decent company. It probably increases Elon's share of the combined entity. It delivers on a promise to investors that he will make money for them, even as the underlying businesses are lousy.

I'm confused about the level of conversation here. Can we actually run the math on heat dissipation and feasibility? A Starlink satellite uses about 5K Watts of solar power. It needs to dissipate around that amount (+ the sun power on it) just to operate. There are around 10K starlink satellites already in orbit, which means that the Starlink constellation is already effectively equivalent to a 50 Mega-watt (in a rou…

> A Starlink satellite uses about 5K Watts of solar power. It needs to dissipate around that amount (+ the sun power on it) just to operate.

This isn't quite true. It's very possible that the majority of that power is going into the antennas/lasers which technically means that the energy is being dissipated, but it never became heat in the first place. Also, 5KW solar power likely only means ~3kw of actual electrical consumption (you will over-provision a bit both for when you're behind the earth and also just for safety margin).

Re: Data centers in space makes no sense

#390

Post by [deleted] » Wed, Feb 04, 2026, 3:08 AM UTC

TurdF3rguson wrote: post #299

lancewiggs wrote: post #177

Earlier quoted context omitted.

It's exiting the 5th best social network and the 10th (or worse) best AI company and selling them to a decent company. It probably increases Elon's share of the combined entity. It delivers on a promise to investors that he will make money for them, even as the underlying businesses are lousy.

> 10th (or worse) best AI company You might only care about coding models, but text is dominating the market share right now and Grok is the #2 model for that in arena rankings.

[deleted]