Elon Musk’s ambitious plan to send thousands of Starlink satellites into space is giving rise to a new concern. While these satellites have made high-speed internet access possible in remote parts of the world, scientists are warning that their growing number could be damaging the planet’s stratosphere, a key layer of the atmosphere.

According to astrophysicist Jonathon McDowell, the satellites’ reentry into Earth’s atmosphere may release materials that harm the stratosphere. He warned that this could lead to serious health problems such as skin cancer and cataracts over time.

Thousands of satellites, mounting space debris

Reports suggest that one or two Starlink satellites deorbit every day, adding to the already growing problem of space junk. McDowell estimates that there are now over 25,000 pieces of debris, including defunct satellites and broken parts, orbiting Earth.

According to Spaceflight Now, SpaceX currently has around 8,000 satellites in orbit, with plans to launch thousands more. By the end of 2025, the company is expected to have over 2,000 additional satellites in space.

FAA warns of potential danger

The Federal Aviation Administration (FAA) had already issued a warning in 2023, cautioning that Starlink satellites could injure or kill someone within the next 10 years if debris survives reentry. The agency estimates that 28,000 fragments could fall back to Earth over the next few years.

Low-orbit satellites typically last five to seven years before they begin to fall back toward Earth. McDowell told EarthSky that based on current trends, up to five satellites a day could re-enter Earth’s atmosphere in the coming years.

Musk has rejected the growing concerns. In a statement to the FAA, he said, “SpaceX’s satellites are designed and built to fully demise during atmospheric reentry during disposal at the end of life, and they do so.”
 However, earlier this year, he admitted that “not all satellites fully disintegrate upon reentry.”

Threat of Kessler syndrome

Experts are also worried about the Kessler Syndrome, a dangerous chain reaction where objects in orbit start colliding with one another, creating even more debris. McDowell warned that the region between 600 and 1,000 kilometres above Earth is especially at risk, calling it a zone “full of old Soviet rocket stages” and other fragments.

If such collisions become frequent, space could turn into a dangerous debris field, making future missions and satellite launches much more difficult.