The Destruction of the Night Sky

There are two proposals before the U.S. Federal Communications Commission right now that would do horrifying things to the night sky. Both are currently open to public comment through March 6 and 9, and I’m gearing up to submit a couple of comments. The FCC is the federal agency that regulates satellite launches in the United States, and they are now in the practice of rubber stamping an awful lot of these.

The first proposal is from a company called Reflect Solar that wants to put giant mirrors in space for the purpose of turning night into day for selected localities, in particular solar farms. They plan to start with an test satellite in 2026 with an 18 meter mirror, and then by 2030 have 4000 satellites in orbit at an altitude of 625 km. Eventually they imagine orbiting 250,000 satellites. The math for the amount of solar energy one can obtain this way absolutely does not work out, but even the 4000-satellite plan would be catastrophic for both professional and amateur astronomy. Visual astronomy would become an extremely risky activity, since accidentally glimpsing the reflected light in a telescope or binoculars could cause permanent eye damage.

Not to be outdone, everybody’s favorite archvillain Elon Musk is wanting to orbit up to 1,000,000 satellites for spaceborne AI data centers. There are presently 14,000 active satellites in space and low earth orbit is already getting crowded. One risk is Kessler syndrome — that is, collisions from space debris causing the generation of more debris in a chain reaction, rendering the entire orbital zone unusable. Another is impacts on atmospheric chemistry as tens of thousands of satellites burning up when they reenter may contribute to ozone depletion and climate change. Advocates of space data centers also tend to neglect the laws of physics. It is a lot harder to cool down a data center in space than on Earth, since due to the vacuum of space the only mechanism for heat transfer is radiation, not conduction or convection. (This is why vacuum thermoses keep their contents hot or cold.)

Both these proposals are now getting mainstream media coverage, such as in the New York Times and the Washington Post. The organization DarkSky International has a web page on how to comment on the proposals.