Orbital AI data centers could work, but they might ruin Earth in the process

At the start of the month, Elon Musk announced that two of his companies — SpaceX and xAI  — were merging , and would jointly launch a constellation of 1 million satellites to operate as orbital data centers. Musk's reputation might suggest otherwise, but according to experts, such a plan isn't a complete fantasy.

However, if executed at the scale suggested, some of them believe it would have devastating effects on the environment and the sustainability of low Earth Earth orbit.      Musk and others argue that putting data centers in space is practical given how much more efficient solar panels are away from Earth's atmosphere.

In space, there are no clouds or weather events to obscure the sun, and in the correct orbit, solar panels can collect sunlight through much of the day.

In combination with declining rocket launch costs and the price of powering AI data centers on Earth, Musk has said that within three years space will be the cheapest way to generate AI compute power.  Ahead of the billionaire's announcement, SpaceX filed an eight-page application with the Federal Communications Commission detailing his plan.

The company hopes to deposit the satellites in this massive cluster in altitudes ranging between 500km and 2000km. They would communicate with one another and SpaceX's Starlink constellation using laser "optical links." Those Starlink satellites would then transmit inference requests to and from Earth.

To power the entire effort, SpaceX has proposed putting the new constellation in sun-synchronous orbit, meaning the spacecraft would fly along the dividing line that separates the day and night sides of the planet.  What a data center would endure in orbit Almost immediately the plan was greeted with skepticism . How would SpaceX, for instance, cool millions of GPUs in space?

At first glance, that might seem like a weird point to get hung up on — much of space being around -450 Fahrenheit — but the reality is more complicated. In the near vacuum of space, the only way to dissipate heat is to slowly radiate it out, and in direct sunlight, objects can easily overheat.

As one commenter on Hacker News succinctly put it, "a satellite is, if nothing else, a fantastic thermos." Scott Manley, who, before he created one of the most popular space-focused channels on YouTube, was a software engineer and studied computational physics and astronomy, argues SpaceX has already solved that problem at a smaller scale with Starlink.

He points to the company's latest V3 model, which has about 30 square meters of solar panels. "They have a bunch of electronics in the middle, which are taking that power and doing stuff with it. Now, some of that power is being beamed away as radio waves, but there's a lot of thermal power that's being generated and then having to be dissipated.

So they already have a platform that's running electronics off of power, and so it's not a massive leap to turn into something doing compute." The larger V3 @Starlink satellites that will deploy from Starship will bring gigabit connectivity to users and are designed to add 60 Tera-bits-per-second of downlink capacity to the Starlink network.