NASA space probe expected to reenter the atmosphere with a chance of raining debris
March 10, 2026
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NASA space probe expected to re-enter atmosphere with chance of raining debris
The Van Allen A probe, which studied how our planet was protected from harmful space radiation, could fall to Earth this evening. Here’s what you need to know
An artist’s rendition depicts NASA’s twin Van Allen probes orbiting in Earth’s magnetic field to explore radiation belts.
One of NASA’s spacecraft could re-enter the atmosphere around 7:45 p.m. EDT tonight. The agency warned that there is a 1 in 4,200 risk of harm to people due to potential debris.
When the 600-kilogram Van Allen A probe re-enters Earth’s atmosphere, most of it will burn up, but NASA expects some parts to survive the journey, the agency said Monday. The exact timing of the event is unclear: the space agency says the 7:45 p.m. EDT estimate has a window of uncertainty of plus or minus 24 hours.
The spacecraft’s orbit is very elliptical, so “the exact time of its re-entry is still very uncertain,” says Jonathan McDowell, an astrophysicist who tracks satellites and space launches. “Based on the latest Space Force data, it may already be down, or it may not be until late Wednesday evening.”
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The probe is one of two sister spacecraft launched in 2012 to study the “Van Allen belts” – bands of protons and electrons that envelop Earth and protect our planet from weather and harmful space radiation. The mission ended in 2019 when the probes ran out of fuel.
The Van Allen Belts are a harsh region and can damage spacecraft and astronauts alike. Remarkably, the probe is not expected to return to Earth until 2034, NASA said, but due to a “much more active than expected” solar cycle, it is returning sooner than expected.
The NASA memo does not clearly specify where Probe A will enter the atmosphere or where debris might fall; NASA and the US Space Force are following its path. (NASA did not immediately respond to a request for comment from Scientific American.) But the agency stressed that the risk of any harm to humans is “low,” about one in 4,200. Most of the Earth’s surface is covered in water, so parts of the probe are most likely to hit the ocean, minimizing the risk to humans. However, for context, the risk of danger to anyone is one in 4,200 is higher than the chances of a single person being struck by lightning in their lifetime or a diver or surfer being bitten by a shark.
The probes served researchers well during their time in orbit: they helped discover an entire radiation belt that was previously unknown to scientists.
“The Van Allen probes rewrote the textbook on the physics of radiation belts,” Sasha Ukhorskiy, a project scientist at the Johns Hopkins Applied Physics Laboratory who worked on the mission, said in a statement in 2019 when the probes retired. “The spacecraft used instruments with unique capabilities to reveal features of the radiation belt that were virtually invisible to previous sensors, and discovered many new physical mechanisms of radiation belt acceleration and loss.”
Editor’s Note (03/10/26): This is a breaking news story and may be updated.
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