The Sun’s unpredictable outbursts are causing satellites to return to Earth sooner than anticipated, occasionally leaving debris behind.
The Sun is currently approaching the peak of its 11-year activity cycle, known as solar maximum. During this period, the Sun’s eruptions trigger powerful geomagnetic storms that affect Earth’s atmosphere.
These geomagnetic storms heat and expand Earth’s upper atmosphere. This expansion increases atmospheric drag on satellites in low Earth orbit (LEO), effectively pulling them back to Earth faster.
Research by NASA’s Goddard Space Flight Center, particularly on SpaceX’s Starlink satellites, has shown that during geomagnetic storms, satellites re-enter the atmosphere much quicker. In some cases, a satellite’s lifespan can be reduced by up to 10 days and this will keep increasing. The lifespan of these satellites is few years ( 7 to 10 years max), in one instance, 37 Starlink satellites re-entered in about five days instead of the typical 15+ days.
The issue is magnified by the proliferation of “mega-constellations” like Starlink, which involve thousands of satellites. SpaceX alone has launched over 7,000 Starlink satellites, with plans for tens of thousands more, leading to an unprecedented rate of satellite launches and re-entries.
While accelerated re-entry can be beneficial by removing dead satellites from orbit more quickly, reducing space debris, it also presents challenges. It could limit the ability to operate satellites in very low Earth orbit (below 400 kilometers).
A major concern is the possibility of satellites not burning up completely upon re-entry. While satellites are designed to disintegrate in the atmosphere, stronger re-entries increase the chance of fragments reaching the ground.
A recent example is the 2.5 kg piece of a Starlink satellite that was found on a farm in Saskatchewan, Canada. Environmental scientists also raise alarms about the long-term effects of satellite combustion, as materials like aluminum oxide can be released into the mesosphere