Earthquake sensors can track space junk that crashes back to Earth

At least three large pieces of space debris — old satellites and spent rocket stages — fall back to Earth every day on average, but researchers have only a very limited understanding of where these potentially dangerous fragments land and what happens to them in the atmosphere. A new method, based on sonic boom tracking by earthquake sensors, could provide real-time information about the hurtling debris fragments’ whereabouts. In November 2022, Spain and France shut parts of their airspace for about 40 minutes as a giant piece of a Chinese rocket was predicted to potentially come crashing down in southern…