The risk of collision of satellites in the Earth’s orbit has decreased to only 2.8 days

A new study reveals that, in a scenario in which satellites in Earth’s orbit suddenly lose the ability to maneuver: for example due to extreme solar storms or global communication disruptions, the first major collision could occur in as little as 2.8 days.

According to Princeton researchers, led by Sarah Till, the risk is escalating due to the explosive growth in the number of satellites in low Earth orbit. While in 2018 there were about 4,000 active satellites in orbit, today there are more than 14,000, and SpaceX Starlink alone has more than 9,000 spacecraft at altitudes of 340 to 550 kilometers.

Researchers warn that scenarios such as powerful solar storms, mass power outages, or errors in GPS and trajectory planning systems can instantly disable collision avoidance systems. This would create a chain reaction of collisions that would render certain orbits virtually unusable.

SpaceX

To assess the risk more accurately, scientists have developed a new model called CRASH Clock (Collision Risk Analysis Simulation Hourglass). The model simulates how quickly the first collision would occur if all satellites suddenly lost their ability to maneuver. Before the introduction of Starlink in 2018, that interval was 121 days. In 2025, it dropped to just 2.8 days!

Scientists believe that a global breakdown is unlikely, but not impossible. An example from May 2024 showed that solar storms can cause serious disturbances when hundreds of Starlink satellites registered “ripples” in orbit.

History also records real collisions: the most famous is the one from 2009 between the active Iridium satellite and the defunct Russian Cosmos, which left hundreds of fragments still in orbit.

However, the global race for satellite constellations is just heating up. Amazon has launched Project Kuiper, while China is planning tens of thousands of satellites under the Guowang and Tianfan projects. According to estimates, this would further shorten the CRASH Clock and increase the risk, writes MSN.

Professor Hugh Lewis of the University of Birmingham warns: “We are building a house of cards. The more cards we add, the bigger the collapse will be when it happens.”