Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Thermodynamics rules future orbital data centers

spectrum.ieee.org

Post reply on HN
Print view View original

91–100 of 113 posts

Re: Thermodynamics rules future orbital data centers

#91

Post by bluecalm »

davidkwast wrote: post #47
bluecalm wrote: post #37

Earlier quoted context omitted.

The plan is to launch from Earth in the beginning stages and then switch to launching from the Moon which has no atmosphere so you don't need rockets and can use an electromagnetic gun instead. That requires satellite manufacturing on the Moon and I guess the minerals required will come from asteroid mining. That's my understanding of what Elon said about how it's going to work.

So the majority of the hardware should stay on the moon where latency isn't so critical. There the cooling won't be the problem.

Elon said they will manufacture big heavy parts on the Moon to reduce the mass they need to use rockets for and maybe ship GPUs from Earth. It sounds like a science-fiction to me but what do I know. You can watch the full interview here:

https://www.youtube.com/watch?v=D_1j5dVWNYI

Re: Thermodynamics rules future orbital data centers

#92

Post by OutOfHere »

fulafel wrote: post #83
OutOfHere wrote: post #70

Earlier quoted context omitted.

That's an environmental and financial cost, but it's a one time cost. For datacenters on Earth, the emissions are continuous.

Are there going to be self sustaining server factories in space? The hw needs updating every few years.

How do we bootstrap to the point where we eventually have factories in space?

If it were up to me, I would be researching and optimizing non-chemical propulsion, also green synthetic fuels for launches. Unfortunately, we will have to leave that for some firm other than SpaceX to develop.

Re: Thermodynamics rules future orbital data centers

#93

Post by octaane »

Science fiction beat the author of this article to the punch re: novel cooling solutions in space. The author proposes squirting oil from one arm, through open vacuum, to another arm - the oil droplets radiate the heat en route from arm 1 to arm 2. However, like most modern tech, science fiction writing has anticipated it. In the book Saturns Run (2015), by John Stanford and Ctien, their spaceship cools down it's megawatt nuclear reactor by using a eutectic metal as coolant, which runs as a molten ribbon through open vacuum from arm 1 to arm 2.

Re: Thermodynamics rules future orbital data centers

#94

Post by spaceclay »

cucumber3732842 wrote: post #61
PowerfulWizard wrote: post #44

Earlier quoted context omitted.

To remove heat by radiation there's a big benefit to running the GPUs hotter as the radiation will be proportional to the fourth power of temperature. This resource is using 85 deg C versus 60 deg C for OP which will improve cooling performance. If Nvidia/SpaceX can make the chips run at a higher temperature that would help a lot although I assume it would have already been done if it were possible. Another option is…

Could they run the chips at "normal" temperatures and then heat pump that all into some other mass that lives at "aerospace alloy" temperatures and radiates it away more efficiently?

[dead]

Re: Thermodynamics rules future orbital data centers

#95

Post by cornholio »

PowerfulWizard wrote: post #44
tristanj wrote: post #5

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.

To remove heat by radiation there's a big benefit to running the GPUs hotter as the radiation will be proportional to the fourth power of temperature. This resource is using 85 deg C versus 60 deg C for OP which will improve cooling performance. If Nvidia/SpaceX can make the chips run at a higher temperature that would help a lot although I assume it would have already been done if it were possible. Another option is…

If radiator temperature is critical you can just run a heat pump to boost it. Modern heat pumps can get pretty close to the Carnot limit for the temperature interval, for example a pump cooling to 300K and dumping out heat at 400K (125°C) will have a theoretical COP limit of 4 and a practical limit of 2.5-3.

That means that for every 3 units of heat your chips emit, you will use a 4th unit to spin the pump. If your panels generate 150kW, you will only have 113kW available for compute and the rest is cooling. Radiators will more than halve vs 340K operation, so it's net beneficial.

It's all a giant techno-economic optimization problem: the extra mass of solar panels you need vs saved radiators vs mass of the pump, the die temperatures you achieve and corresponding performance, durability and chip price point etc.

Re: Thermodynamics rules future orbital data centers

#96

Post by [deleted] »

PowerfulWizard wrote: post #87
mc32 wrote: post #81

Earlier quoted context omitted.

Sorry but wouldn’t space based DCs need radiation hardened parts which are typically a few generations behind SoTA? Do the centers deploy massive shields to protect the electronics?

I haven't heard of that being a problem for Starlink, whatever they've done there seems to be working. The Orbital AI would be at a higher orbit but still within LEO which reduces the radiation. I wonder if occasional bit flips even matter for typical AI calculations. Quantization seems to suggest a lot of the lower bits aren't all that important. Either way SpaceX has already had success building systems with commer…

[deleted]

Re: Thermodynamics rules future orbital data centers

#97

Post by rstuart4133 »

lispisok wrote: post #82
tristanj wrote: post #5

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.

The point of datacenters in space is about control not economics. They dont want the masses which they are trying to replace with AI and robots to have access to the datacenters running everything.

Why did the word "skynet" pop into my mind?

Re: Thermodynamics rules future orbital data centers

#98

Post by brokenmachine »

its-summertime wrote: post #62
krunck wrote: post #50

Earlier quoted context omitted.

They'll pay the price if it means their data centers are immune to the anger of the commoners who are being surveilled, analyzed, and manipulated by systems running on these data centers.

I think the more likely goal would be immunity to regulation.

[dead]

Re: Thermodynamics rules future orbital data centers

#99

Post by brokenmachine »

bluecalm wrote: post #37
giraffe_lady wrote: post #13

Earlier quoted context omitted.

It assumes $44/kg to launch into orbit. Idk where that came from if it's a musk claim or what but it's ludicrous against current costs. Currently still at thousands/kg and dropping but nowhere near $44 and I haven't heard anyone claim that's likely who isn't selling a rocket company.

The plan is to launch from Earth in the beginning stages and then switch to launching from the Moon which has no atmosphere so you don't need rockets and can use an electromagnetic gun instead. That requires satellite manufacturing on the Moon and I guess the minerals required will come from asteroid mining. That's my understanding of what Elon said about how it's going to work.

Asteroid mining? This is the most ridiculous thing ever. How this half baked snake oil salesman gets anyone to invest in his companies amazes me.

Re: Thermodynamics rules future orbital data centers

#100

Post by bigbadfeline »

PowerfulWizard wrote: post #87
mc32 wrote: post #81

Earlier quoted context omitted.

Sorry but wouldn’t space based DCs need radiation hardened parts which are typically a few generations behind SoTA? Do the centers deploy massive shields to protect the electronics?

I haven't heard of that being a problem for Starlink, whatever they've done there seems to be working. The Orbital AI would be at a higher orbit but still within LEO which reduces the radiation. I wonder if occasional bit flips even matter for typical AI calculations. Quantization seems to suggest a lot of the lower bits aren't all that important. Either way SpaceX has already had success building systems with commer…

> I haven't heard of that being a problem for Starlink, whatever they've done there seems to be working.

Starlink doesn't need GPUs, they use hardened chips. The first question is, can whatever works as a 2nm GPU work where Starlink is?

The second question is even funnier: Starlink satellites have a limited lifespan and regularly burn up in the atmosphere when they fall back to Earth - that's due to the need to fly them at low altitudes where, coincidentally, the radiation is lower.

Where then will the flying data centers be - high with higher radiation or low with a higher fall rate? And I doubt those heavy birds are going to burn up fully before hitting somebody's head.

Post reply on HN