SpaceX's Starlink megaconstellation may be hindering ozone healing process
SpaceX's Starlink megaconstellation, which currently consists of nearly 6,000 satellites, may be impeding the Earth's atmosphere from healing itself, a new study suggests. Researchers from the University of Southern California have calculated the potential harm caused by these satellites, releasing harmful substances like aluminum oxides into the upper atmosphere, as they burn up during their reentry. The study indicates that these decommissioned satellites could be contributing to "significant ozone depletion."
Satellite reentry's overlooked environmental impact
The study marks a shift in focus from the pollutants released by rockets during launch, to the environmental impact of thousands of retired and malfunctioning satellites burning up in the atmosphere. This shift is particularly significant as SpaceX plans to launch tens of thousands more Starlink satellites. "Only in recent years have people started to think this might become a problem," said Joseph Wang, co-author of the study and astronautics researcher at the University of Southern California.
Aluminum oxide levels could rise significantly
The difficulty in obtaining accurate readings from pollutants released by satellites during reentry means that scientists can only estimate their environmental impact. The researchers estimated that atmospheric aluminum levels increased by nearly 30% in 2022 due to the interaction of common metals used in satellite construction. They found that a 250kg satellite produces roughly 30kg of aluminum oxide nanoparticles during reentry, which might take up to 30 years to descend into the stratosphere.
Potential annual increase in chemical compounds
If satellite constellations like SpaceX's continue to grow as planned, atmospheric aluminum oxide levels could rise by a staggering 646% annually. The researchers stressed that understanding these environmental impacts is still in its early stages. "The environmental impacts from the reentry of satellites are currently poorly understood. As reentry rates increase, it is crucial to further explore the concerns highlighted in this study," they noted in their paper.
