As Earth’s orbit continues to fill up with discarded rockets and old satellites, experts say planes could be at risk from falling debris.

“There is a real risk,” Aaron Boley, associate professor of astronomy and astrophysics at the University of British Columbia, told CTVNews.ca. “The use of space is just expanding, and when we put big objects into orbit, they eventually come down, and if left uncontrolled, it’s a hazard to people on the ground, at sea, and on airplanes.”

Boley and a colleague recently wrote an article on the subject, arguing that the recent surge in flights and satellite launches could lead to an aviation tragedy unless efforts are made to curb and better manage uncontrolled missile re-entry track, regulate and respond to . Boley’s co-author, UBC political scientist Michael Byers, says there is a 10 percent chance that space debris will cause one or more deaths in the next decade.

“If, in principle, there can be controlled reentry, then there should be controlled reentry,” Boley said. “And if there absolutely can’t be controlled re-entry, then other things need to be done so that we have as much information as possible to make informed decisions, and we don’t just suddenly react to every new big object that comes down.” That’s what’s happening now.”

Satellites are usually launched into orbit by rockets, which are then often exited and eventually fall back to Earth in so-called uncontrolled re-entry.

“The atmosphere slowly decays that orbit and eventually it re-enters and you don’t know where on its trajectory it will eventually re-enter,” Boley explained.

In contrast, controlled re-entry means that a rocket or spacecraft has a planned return route, like when astronauts return home from the International Space Station.

“They’ve got things like reignitable thrusters, which have a lot of rockets, and they can then direct the trajectory to go somewhere, say, in the ocean, that’s out of the way,” Boley said. “That extra fuel is weight and that then takes away from the payload delivery… So there’s absolutely a cost involved.”

Although no known case of missile or satellite debris hitting an aircraft, several past incidents have raised alarms. In May 2020, a Chinese missile made an uncontrolled re-entry, scattering debris overhead Ivory Coast. In November 2022, France and Spain closed parts of their airspace to another Chinese missile, which eventually crashed into the Pacific Ocean.

“So they had this sudden rerouting of planes and it caused big delays, there was a big economic hit with it,” Boley said.

A look at the Canadian government’s database of aviation incidents shows that space debris may also fall over or near the country, as on Jan. 18, 2007, when a United Airlines flight “dropped a large flaming ball with … debris or debris falling.” assume” reported flying over the arctic.

“It’s largely a Wild West,” Boley said of existing missile launch rules and regulations. “When a state launches a satellite and puts something into orbit and lets it come down uncontrolled, it is doing what is called risk exporting. So he lets the rest of the world take on a lot of the risk of that particular launch.”

Some countries and aviation associations, such as the Air Line Pilots Association and the International Civil Aviation Organization, have started to take notice.

In March 2023, UBC’s Outer Space Institute released its “Montreal Recommendations,” which included calls for “global standards” for uncontrolled reentry at times when over seven thousand objects are in low Earth orbit.

“Tens of thousands of additional satellites will be licensed, while hundreds of thousands more satellites are proposed… many of which will re-enter Earth’s atmosphere in the years and decades to come,” it said. “Because of their relative impact velocity, even small or light debris, which may be harmless to people on the ground, can fatally damage an aircraft in flight or otherwise require emergency response by its crew.”

The paper was signed by Boley and Byers at UBC, as well as retired astronaut and former Canadian cabinet minister Marc Garneau, the inspector general of the French space agency and the US Air Force’s chief of space security.

Boley hopes the international community will come up with clear guidelines before uncontrolled missile re-entry causes an airplane disaster.

“Ultimately, [we’re] Throwing things up and just letting things collapse under the paradigm that the Earth is so big, we don’t need to worry about that,” Boley said. Oceans are so big we don’t need to worry about this plastic that we use throw in; The atmosphere contains so much material that we don’t have to worry about all the carbon we’re adding to it. We do that again and again.”