A new study shows that earthquake monitoring networks can track falling space debris by detecting the sonic booms produced during atmospheric reentry, sometimes more accurately than radar. The Associated Press reports: Scientists reported Thursday that seismic readings from sonic booms that were generated when a discarded module from a Chinese crew capsule reentered over Southern California in 2024 allowed them to place the object’s path nearly 20 miles (30 kilometers) farther south than radar had predicted from orbit. Using this method to track uncontrolled objects plummeting at supersonic speeds, they said, could help recovery teams reach any surviving pieces more quickly — crucial if the debris is dangerous.
“The problem at the moment is we can track stuff very well in space,” said Johns Hopkins University’s Benjamin Fernando, the lead researcher. “But once it gets to the point that it’s actually breaking up in the atmosphere, it becomes very difficult to track.” His team’s findings, published in the journal Science, focus on just one debris event. But the researchers already have used publicly available data from seismic networks to track a few dozen other reentries, including debris from three failed SpaceX Starship test flights in Texas. […]
Fernando is looking to eventually publish a catalog of seismically tracked, entering space objects, while improving future calculations by factoring in the wind’s effect on falling debris. In a companion article in Science, Los Alamos National Laboratory’s Chris Carr, who was not involved in the study, said further research is needed to reduce the time between an object’s final plunge and the determination of its course. For now, Carr said this new method “unlocks the rapid identification of debris fall-out zones, which is key information as Earth’s orbit is anticipated to become increasingly crowded with satellites, leading to a greater influx of space debris.”