Measuring Radio Leaks from 36,000 Kilometres Up

Radio astronomers hunting for the faint whispers of the early universe face an unexpected threat from above: satellites designed to be silent are leaking radio noise into space. New research using the Murchison Widefield Array has set the first limits on unintended radio emissions from distant geostationary satellites, revealing that most remain mercifully quiet in the frequency range crucial for next-generation telescopes. The findings offer cautious hope that the Square Kilometre Array, set to become the world’s most sensitive radio telescope, might avoid the radio pollution crisis now plaguing observations of low Earth orbit satellites.