The environmental cost of putting data centers in space

When Space X filed an FCC application earlier this year proposing to launch a million satellite data centers into orbit, the company argued the project would have no meaningful environmental impact. On Space X’s website, Elon Musk made the case for space-based AI infrastructure in simpler terms: “It’s always sunny in space,” he wrote, arguing that orbital data centers are “obviously the only way to scale.” When Space X filed an FCC application earlier this year to launch a million satellite data centers into space, the company said that the plan wouldn’t have any environmental impact. But researchers say the climate calculus is far more complicated than that. Yes, orbital data centers could theoretically run around the clock on solar power. But the tradeoffs extend far beyond electricity consumption. “The social and environmental consequences are far greater than what we’re currently looking at with Earth-based alternatives,” says Peter Howson, a researcher at Northumbria University who recently authored a paper examining the risks and challenges of space-based computing infrastructure. First, the emissions from each rocket launch are large—a single SpaceX Starship launch burns around a kiloton of liquid methane and produces as much climate pollution as a small city does in a year. Black soot emitted from rockets is long-lasting in the upper atmosphere and can cause significantly more global warming than the same pollution on the ground. “Soot that comes out of the tailpipe in a car normally lasts maybe a few weeks in the lower atmosphere,” Howson says. “But when you put it into the upper atmosphere, it could stay there for years.” Water vapor emissions also act as a potent greenhouse gas. Around 2 million liters of water are also used to protect launch pads at every launch, and that process can wash toxic dust and debris into local ecosystems. In Texas, the state’s Commission on Environmental Quality and the EPA previously found that SpaceX repeatedly violated t