In January 2025, 120 SpaceX Starlink satellites re-entered Earth's atmosphere, disintegrating as they burned up during re-entry. The increasing frequency of such incidents is raising concerns among scientists and environmentalists about the impact of these satellites on atmospheric pollution.

Elon Musk-led SpaceX developed the Starlink satellite network to provide “low-cost internet access” to remote locations. However, the rate of satellites in orbit is increasing as the constellation keeps expanding.

The 120 Starlink satellites that re-entered Earth's atmosphere turned into spectacular fireballs as they burned up.
Why are Starlink satellites falling?
Four to five of these satellites burned up daily in January, Astronomer Jonathan McDowell noted.


SpaceX replaces older satellites with newer ones, and the lifespan of around 500 of the first-generation Starlink satellites has already ended.

Nearly 7,000 satellites are being operated by SpaceX and now the company is planning to refresh its satellite network every five years. As the re-entries of satellites are planned, atmospheric pollution is a major concern now.

Scientists warn of environmental risks
The disintegration of these satellites results in the release of metallic vapours into the atmosphere. In 2023, satellite debris was found in aerosols 60,000 feet above Alaska. Scientists fear aluminium oxides from re-entries could harm the ozone layer.

These oxides have increased eightfold from 2016 to 2022, research shows. Scientists have already warned that this could change atmospheric chemistry in unpredictable ways. Despite concerns, SpaceX says its satellites fully burn up, leaving no debris.

Scientists say the space debris is not limited to Starlink satellites. Studies suggest that there is a 26 per cent annual chance of rocket parts falling. Although this risk is low, debris could disrupt air travel and airlines might face additional costs due to uncontrolled entries.

Amid all the concern, SpaceX says their satellites end up burning fully, leaving no debris.
Life of Starlink satellites is five years
Generally, SpaceX launches satellites in batches of 20 or more. These satellites are designed to stay in low earth orbit for around five years before they are deorbited and allowed to burn up in Earth's atmosphere.

Once the life of a Starlink satellite completes, it uses electric thrusters to lower the altitude to around 155 miles (250 kilometres), at this point the atmospheric drag further slows it down till it falls from space, McDowell said. This process takes a week to complete.