One solar storm could trigger a catastrophic collision in orbit
Margo Anderson
21 Jan 2026
Thousands of satellites are tightly packed into low Earth orbit, and the overcrowding is only growing.
Scientists have created a simple warning system called the CRASH Clock that answers a basic question: If satellites suddenly couldn’t steer around one another, how much time would elapse before there was a crash in orbit? Their current answer: 5.5 days.
The CRASH Clock metric was introduced in a paper originally published on the Arxiv physics preprint server in December and is currently under consideration for publication. The team’s research measures how quickly a catastrophic collision could occur if satellite operators lost the ability to maneuver—whether due to a solar storm, a software failure, or some other catastrophic failure.
To be clear, say the CRASH Clock scientists, low Earth orbit is not about to become a new unstable realm of collisions. But what the researchers have shown, consistent with recent research and public outcry, is that low Earth orbit’s current stability demands perfect decisions on the part of a range of satellite operators around the globe every day. A few mistakes at the wrong time and place in orbit could set a lot of chaos in motion.
But the biggest hidden threat isn’t always debris that can be seen from the ground or via radar imaging systems. Rather, thousands of small pieces of junk that are still big enough to disrupt a satellite’s operations are what satellite operators have nightmares about these days. Making matters worse is SpaceX essentially locking up one of the most valuable altitudes with their Starlink satellite megaconstellation, forcing Chinese competitors to fly higher through clouds of old collision debris left over from earlier accidents.
https://spectrum.ieee.org/kessler-syndrome-crash-clock
Credit: Sarah Thiele, Skye R. Heiland, et al.