Yes cooling is difficult. Half the "solar panels" on the ISS aren't solar panels but heat radiation panels. That's the only way you can get rid of it and it's very inefficient so you need a huge surface.

If you read the Starcloud whitepaper[1], it claims that massive batteries aren't needed because the satellites would be placed in a dawn-dusk sun-synchronous orbit. Except for occasional lunar eclipses, the solar panels would be in constant sunlight.

The whitepaper also says that they're targeting use cases that don't require low latency or high availability. In short: AI model training and other big offline tasks.

For maintenance, they plan to have a modular architecture that allows upgrading and/or replacing failed/obsolete servers. If launch costs are low enough to allow for launching a datacenter into space, they'll be low enough to allow for launching replacement modules.

All satellites launched from the US are required to have a decommissioning plan and a debris assessment report. In other words: the government must be satisfied that they won't create orbital debris or create a hazard on the ground. Since these satellites would be very large, they'll almost certainly need thrusters that allow them to avoid potential collisions and deorbit in a controlled manner.

Whether or not their business is viable depends on the future cost of launches and the future cost of batteries. If batteries get really cheap, it will be economically feasible to have an off-the-grid datacenter on the ground. There's not much point in launching a datacenter into space if you can power it on the ground 24/7 with solar + batteries. If cost to orbit per kg plummets and the price of batteries remains high, they'll have a chance. If not, they're sunk.

I think they'll most likely fail, but their business could be very lucrative if they succeed. I wouldn't invest, but I can see why some people would.

1. https://starcloudinc.github.io/wp.pdf

Servers outside any legal jurisdiction. Priceless.

The best argument I've heard for data centres in space startups is it's a excuse to do engineering work on components other space companies might want to buy (radiators, shielding, rad-hardened chips, data transfer, space batteries) which are too unsexy to attract the same level of FOMO investment...

You need less batteries in orbit than on the ground since you're only in shade for at most like 40 minutes. And it's all far more predictable.

Cooling isn't actually any more difficult than on Earth. You use large radiators and radiate to deep space. The radiators are much smaller than the solar arrays. "Oh but thermos bottles--" thermos bottles use a very low emissivity coating. Space radiators use a high emissivity coating. Literally every satellite manages to deal with heat rejection just fine, and with radiators (if needed) much smaller than the solar arrays.

Latency is potentially an issue if in a high orbit, but in LEO can be very small.

Equipment upgrades and maintenance is impossible? Literally, what is ISS, where this is done all the time?

Radiation shielding isn't free, but it's not necessarily that expensive either.

Orbital maintainence is not a serious problem with low cost launch.

The upside is effectively unlimited energy. No other place can give you terawatts of power. At that scale, this can be cheaper than terrestrially.

I think the upside is that it’s VC fodder. I imagine their thinking went about as far as “wow, what if we like….did AI…but in space?!”

Re: reliable energy. Even in low earth orbit, isn't sunlight plentiful? My layman's guess says it's in direct sun 80-95% of the time, with deterministic shade.

We’re probably thinking of it the wrong way. Instead of a single datacenter it’s more likely we build constellations and then change the way we write software.

There will probably be a lot more edge computing in the future. 20 years ago engineers scoffed at the idea of deploying code into a dozen regions (If you didn’t have a massive datacenter footprint) but now startups do it casually like it’s no big deal. Space infrastructure will probably have some parallels.

Sounds like a great investment for SoftBank

> Reliable energy? Possible, but difficult -- need plenty of batteries

I can see it now - orbiting crypto mines power on at dawn, die off at dusk, Oscar-7 style

You're making lots of assumptions. They can put like 1000 Raspberrypi's which don't need all that much cooling and relatively little energy requirements.

For your other concerns, the risks are worth it for customers because of the main reward: No laws or governments in space! Technically, the datacenter company could be found liable but not for traffic, only for take-down refusals. Physical security is the most important security. For a lot of potential clients, simply making sure human access to the device is difficult is worth data-loss,latency and reliability issues.

Why do you need a lot of batteries with the right orbit can’t you have solar energy 24/7?

Bandwidth - negligible

reliable energy is the only (maybe valid) reason. you can get yourself into a sun synchronous dawn dusk orbit and avoid shading by the earth.

> There's no upside, it's only downsides as far as I can tell.

It's outside of any jurisdiction, this is a dream come true for a libertarian oligarch.