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Thermodynamics rules future orbital data centers

60 pointsby rbanffytoday at 1:29 PM90 commentsview on HN

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tristanjtoday at 3:09 PM

Economics calculator for Orbital vs Terrestrial Data Centers

https://andrewmccalip.com/space-datacenters

You can play around with the cost sliders to estimate the economics, but even being quite optimistic, space data centers cost ~2-3x of their terrestrial counterparts.

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arjietoday at 3:21 PM

Only a single order of magnitude of cost? So a $4b data center on Earth delivers the same value as a $40b data center in Space? So if you have greater than a 95% operating margin and capacity constraints (either due to nation environmental law, power limits, or other such blockers) then this is a no-brainer - a 95% operating margin becomes a 50% operating margin. The return on capital is much much lower so you have to be anticipating cheaper capital, even cheaper costs than this in practice, or something else.

Inference margins are some 70% right now? So it needs quite some work on both sides but this seems to make it seem more achievable than I previously thought.

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Zigurdtoday at 3:45 PM

Remember space manufacturing? When the first modules of ISS were launched 27 years ago, that was supposed to be the next big thing. Space manufacturing, asteroid mining, and space data centers are pipedreams. The capital equipment is too heavy, and 100% forever automated operations are not realistic.

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ge96today at 2:59 PM

I'm excited I think of the Cowboy Bebop episode (Jamming With Edward) where they hunt down a rogue satellite to get data off it.

Also think it would be crazy to have a worm spread across the servers/starlink, would there be an antivirus system onboard or maybe not applicable, says RTOS can get a virus

jobeadtoday at 3:18 PM

Why is everyone so focused on heat when cosmic rays randomly scrambling memory is going to be a much bigger problem?

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solenoid0937today at 6:49 PM

Space datacenters make no sense. Build them in the oceans? Then you can actually fix them as well.

tzstoday at 4:58 PM

There's also the issue of scaling. Say you can make the engineering work for building a data center in space.

Nobody wants to build just one, or even just a handful. Musk has talked about 10000 launches a year for deploying and maintaining data centers.

At that scale pollution becomes a serious issue. It hasn't been a problem so far because we haven't launched a lot of rockets. Cumulatively the world has under about 8000 orbital launches and under 40000 launches that were not orbital but reached the stratosphere.

Orbital rocket emissions have an impact far beyond what you might expect just from looking at the mass of what they emit, because they emit much of it the upper atmosphere. Many things that when emitted near the surface are only a local problem become a global problem if you emit them in the upper atmosphere.

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inopinatustoday at 3:54 PM

“Solved problem”. https://en.wikipedia.org/wiki/Matrioshka_brain

It merely remains to build one.

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melodyogonnatoday at 4:16 PM

All very interesting, but I'd wait and see what people with real-world experience running Spacecraft can come up with before dismissing the entire endeavor.

CuriouslyCtoday at 3:15 PM

Honestly, data centers in the ocean make so much more sense than data centers in space it's kind of silly, but Mr Moneybags owns a rocket company he's trying to pump and dump, not a submarine company, so here we are.

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khueytoday at 3:37 PM

I'm not usually an "AI is going to kill us all" kind of person but on the off chance we do get Skynet/etc why would we give the machines the literal high ground?

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ericdtoday at 4:29 PM

Anyone know why everyone focuses on the radiators, when the solar panels are significantly larger?

ForHackernewstoday at 3:20 PM

Tyranny of the rocket equation[0] makes it hard for me to conceive how an orbital data centre could ever make sense.

If you just want to escape permitting laws, why not float it in international waters? That's a much more accessible and hospitable environment than LEO.

[0] https://archive.is/qp4gP

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jmyeettoday at 4:58 PM

Let's be honest. The only reason orbital data centers are a talking point at all is to justify the stratospheric SpaceX valuation for the IPO. There's literally no other reason.

Everybody who knows anything about data centers understands this. You don't even need to get into the thermodynamics of cooling where the only option is radiating away heat. Terrestial data centers have to use water cooling because the heat generation is so significant.

The real problem is failure. When you have a lot of servers, things fail all the time. Hard drives, SSDs, RAM chips, GPUs, motherboard, etc. Servers are designed to be able to quickly replace parts. If your data center is in orbit, these parts will just fail and there is no repair. There's certainly no economic repair.

If I remember my numbers rightly, at a company like Amazon or Google, the ratio is (IIRC) 1 FTE per 10,000 servers, meaning if you have 10,000 servers, 1 FTE will spend their entire time just replacing parts. A good hardware tech will have a pool of known good parts. When a server detects a fault, they'll go and replace probably everything with known good parts and then figure out what's wrong later. In GPU heavy DCs I suspect 1 FTE can cover fewer than that just because the heat management is much more complicated.

I really can't believe we're still talking about this. It borders on journalistic malpractice to even suggest this is a realistic possibility.

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poppafuzetoday at 3:59 PM

Gravity. That's what rules orbital-anything.

OutOfHeretoday at 3:55 PM

The best thing for space GPUs would to run at a much high temperature, thereby allowing the radiator to be fairly small. This would require a special high-temperature GPU, with robust radiation protection and error correction, ideally in solar orbit. I have a video https://youtu.be/s7Mv_OcBXI8 covering the approach for heat rejection.

2OEH8eoCRo0today at 3:03 PM

> At ABI Research, where I work as an aerospace analyst, we did a rough total-cost-of-ownership comparison between a data center on Earth and one in space. It showed that the cost to launch and run a GPU in space for a year is at least an order of magnitude higher than the same feat in a terrestrial data center.

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josefritzisheretoday at 3:02 PM

I appreciate the sci-fi quality of this but when the IPO comes remember the "fi" stands for "fiction."

macspoofingtoday at 4:04 PM

>Why Orbital Data Centers Are Harder Than Silicon Valley Thinks

Who thinks they are easy? Elon Musk? The guy that spews obvious (even to him) bullshit like we're going to Mars in the next 5 years?

I don't even want to read the article. It is obvious that Orbital Data Centers have MASSIVE engineering challenges. They may never be cost-effective.