In mid October a mysterious object cracked the windshield of a Boeing 737 at 36,000 feet, prompting online speculation that space debris might have been responsible. While investigators still think the object was likely a weather balloon, the episode highlights a growing trend: about three pieces of old space equipment reenter the atmosphere every day, according to the European Space Agency, and analysts expect the number of satellites in orbit to rise from roughly 12,900 today to as many as 100,000 in a decade. Richard Ocaya, a coauthor of a recent paper on space debris risk, says “the number of such landfall events is increasing” and may rise exponentially in the coming years.
Multiple close calls and localized strikes have been reported recently. In March a 0.7 kilogram metal chunk from the International Space Station pierced a Florida roof. Fragments from rockets and Starlink satellites have fallen near Poznan in Poland and on a farm in Saskatchewan, and incidents have been reported in Australia and Africa. Some manufacturers and operators, including SpaceX, say satellites are “designed for demise,” but testing by space engineers suggests durable components such as tanks and titanium alloys can survive hypersonic reentry. James Beck, who has run wind tunnel tests, warns larger satellites of around 800 kilograms could leave two or three surviving objects on the ground.
Quantifying the hazard is difficult. The Federal Aviation Administration estimated a 2035 risk that one plane per year could suffer a disastrous space debris strike at about 7 in 10,000. Researchers estimate the casualty risk on the ground could be much higher; one study suggests a single human death or injury from debris could reach around 10 percent per year by 2035 under certain assumptions, and the FAA estimated one person might be injured or killed every two years. Predicting precise reentry locations is hard because atmospheric effects introduce large uncertainties. Advances in Artificial Intelligence have improved orbital predictions, but they still cannot fully model the complex physics of reentry. Airspace closures to avoid strikes already create delays and costs, and further adaptation of air traffic control, improved reentry practices, and more controlled deorbits are being discussed as mitigation steps. The European Space Agency estimates only about half of rocket bodies reenter in a controlled way and roughly 2,300 large uncontrolled rocket bodies remain in orbit, meaning reentries and related aviation disruptions are likely to continue.
