I was talking to someone about this the other day. I was part of a team at NASA that developed a cooling system for the ISS and this whole premise makes no sense to me.

1. Getting things to space is incredibly expensive

2. Ingress/egress are almost always a major bottleneck - how is bandwidth cheaper in space?

3. Chips must be “Rad-hard” - that is do more error correcting from ionizing radiation - there were entire teams at NASA dedicated to special hardware for this.

4. Gravity and atmospheric pressure actually do wonders for easy cooling. Heat is not dissipated in space like we are all used to and you must burn additional energy trying to move the heat generated away from source.

5. Energy production will be cheaper from earth due to mass manufacturing of necessary components in energy systems - space energy systems need novel technology where economies of scale are lost.

Would love for someone to make the case for why it actually makes total sense, because it’s really hard to see for me!

It sounds hard but it shouldn't not make sense.

1. Solving cost of launching mass has been the entire premise of SpaceX since day one and they have the track record.

2. Ingress/egress aren't at all bottlenecks for inferencing. The bytes you get before you max out a context window are trivial, especially after compression. If you're thinking about latency, chat latencies are already quite high and there's going to be plenty of non-latency sensitive workloads in future (think coding agents left running for hours on their own inside sandboxes).

3. This could be an issue, but inferencing can be tolerant to errors as it's already non-deterministic and models can 'recover' from bad tokens if there aren't too many of them. If you do immersion cooling then the coolant will protect the chips from radiation as well.

4. There is probably plenty of scope to optimize space radiators. It was never a priority until now and is "just" an engineering problem.

5. What mass manufacture? Energy production for AI datacenters is currently bottlenecked on Siemens and others refusing to ramp up production of combined cycle gas turbines. They're converting old jet engines into power plants to work around this bottleneck. Ground solar is simply not being considered by anyone in the industry because even at AI spending levels they can't store enough power in batteries to ride out the night or low power cloudy days. That's not an issue in space where the huge amount of Chinese PV overproduction can be used 24/7.

> 5. Energy production will be cheaper from earth

Sun-synchronous orbit means solar panels collect the same amount 24/7. I guess that's the #1 benefit. Cheap energy.

> Would love for someone to make the case for why it actually makes total sense, because it’s really hard to see for me!

Elon musk has a history of making improbable-sounding promises (buy a tesla now, by 2018 it will be a self-driving robotaxi earning money while you sleep, humanoid robots, hyperloops).

The majority of these promises have sounded cool enough to enough people that the stock associated with him (TSLA) has made people literal millionaires just by holding onto the stock, and more and more people have bought in and thus have a financial interest in Musk's ventures being seen in a good light (since TSLA stock does not go up or down based on tesla's performance, it goes up or down based on the vibes of elon musk. It is not a car company stock, it is an elon vibes check).

The thing he's saying now pattern matches to be pretty similar, and so given Musk's goal is to gain money, and he gains money by TSLA and SpaceX stock going up, this makes perfect sense as a thing to say and even make minor motions towards in order to make him richer.

People will support it too since it pattern matches with the thing prior TSLA holders got rich off of, and so people will want to keep the musk vibes high so that their own $tsla holdings go to the moon.

Make sense now?

>Ingress/egress are almost always a major bottleneck - how is bandwidth cheaper in space?

Free space optics are much faster than data to/from the ground. If the training workloads only require high bandwidth between sats, this isn’t a real issue.

> Chips must be “Rad-hard” - that is do more error correcting from ionizing radiation - there were entire teams at NASA dedicated to special hardware for this.

They don't do RAD hardening on chips these days, they just accept error and use redundant CPUs.

When they talk about "space" they are, right now, talking about the moon. Which has some gravity. They are putting the data centers on the moon. And the satellites are lunar satellites not earth-orbit satellites. Lonestar physical data center payload landed on the moon in Feb 2025 and Sidus space developing the lunar satellites.