Satellites, Atmosphere, and Space Junk: What the New Filing Means

SpaceX has filed an application with the U.S. Federal Communications Commission to deploy up to one million satellites as orbital data centers. The filing describes systems that would operate between 500 km and 2,000 km above Earth and use laser links and solar power to run AI workloads in space. While the plan aims to reduce energy limits on ground data centers, it would put very large numbers of craft into a few narrow orbital shells.

Scientists have observed cooling and contraction of the upper atmosphere, and this trend has been linked to rising greenhouse gases. As the thermosphere cools, air density at common satellite altitudes falls, so atmospheric drag is reduced and debris can remain aloft longer. Although short-term space weather events can increase drag and speed reentries, the long-term change in density is expected to lengthen satellite lifetimes and challenge debris cleanup.

Studies have also modelled the effect of metal particles from reentering satellites and found that aluminum oxide (alumina) could accumulate in the stratosphere and affect temperatures and winds. Therefore, engineers and regulators will need new tools to manage crowded orbits and to limit long-lived space junk.