Large, uncontrolled space debris reentering Earth’s atmosphere increasingly threatens air travel due to potential airspace closures, according to a new study by three University of British Columbia (UBC) researchers.
The paper, Airspace closures due to reentering space objects, published in Scientific Reports on Jan. 23, warns that “the space industry is imposing risks and costs on the aviation industry, air crews, and passengers.”
Co-author Aaron Boley, associate professor at UBC and co-director of the Outer Space Institute, said there remains a belief that “what we do on orbit doesn’t really matter and doesn’t affect us on Earth.”
Boley explained that the rise in global flights, combined with an increasing number of rocket and satellite components in orbit, heightens the likelihood of major disruptions to air travel due to unplanned reentries.
The study found a 0.8% annual chance of space junk reentry affecting high-density air traffic regions near major airports, while for larger but still busy air travel areas, the chance of disruption increases to 26% per year.
High-risk areas include the northeastern United States, northern Europe, and major cities in the Asia-Pacific region.
According to Boley, these findings reflect a current snapshot, with risks set to grow. Some rocket launches incorporate planned reentries to control when and where debris falls, but most do not.
“When things come back in an uncontrolled way, they do create a casualty risk for people on the ground, at sea, or in airplanes,” Boley said, emphasizing that while individual risk is low, the global impact is significant.
Many defunct satellites and rocket parts orbit in the outer atmosphere, gradually slowing down before falling to Earth. While most break up, some remain intact—sometimes as large as a school bus.
Boley cited an example from early last year when NASA jettisoned a pallet of old batteries from the International Space Station in 2021. Though expected to burn up on reentry, a metal support piece survived, tearing through the roof of a Florida home and embedding in the floor.
Even small debris can be lethal, especially for fast-moving aircraft, potentially leading to tragic outcomes. “It is a low probability that an aircraft will be hit by falling space debris, but it’s not a zero risk by any means—it’s a low-probability, high-risk event,” Boley said.
Beyond direct collisions, the greater concern is authorities preemptively closing airspace during uncontrolled reentries. The study examined a case from November 2022 when a 20-tonne rocket body reentered the atmosphere over the Pacific Ocean. Spanish and French authorities closed sections of airspace, delaying 645 aircraft by an average of 29 minutes.
Boley stressed that the space industry must adopt controlled reentries as a standard practice. “We fundamentally need to stop just abandoning things in orbit. We need to have proper stewardship of that,” he said.
Source: Swifteradio.com
