NASA’s Van Allen Probe A Reenters Earth’s Atmosphere

After nearly 14 years in orbit, NASA’s Van Allen Probe A is expected to reenter Earth’s atmosphere on March 10, 2026, with a window of uncertainty of plus or minus 24 hours. The probe, launched in 2012, has completed its mission to study the Van Allen radiation belts, regions of charged particles surrounding Earth.

Understanding the Van Allen Probes

The Van Allen Probes, A and B, were designed to explore the Van Allen belts – rings of charged particles trapped by Earth’s magnetic field. These belts are crucial to understanding as they shield Earth from harmful cosmic radiation, solar storms, and solar wind that can damage technology and pose risks to humans [NASA]. The probes operated from 2012 to 2019, gathering unprecedented data on these radiation belts.

Reentry Details and Risk Assessment

The U.S. Space Force predicts the approximately 1,323-pound spacecraft will reenter at approximately 7:45 p.m. EDT on March 10, 2026 [NASA]. Whereas most of the spacecraft is expected to burn up during reentry, some components are likely to survive. However, NASA estimates the risk of harm to anyone on Earth is low, approximately 1 in 4,200 [NASA] and [Scientific American].

Mission Accomplishments and Unexpected Factors

Originally designed for a two-year mission, the Van Allen Probes operated for nearly seven years. They were the first spacecraft designed to operate and collect scientific data for an extended period within the radiation belts [NASA]. The mission concluded when both spacecraft ran out of fuel and could no longer maintain their orientation towards the Sun.

The reentry is occurring earlier than initially predicted. NASA engineers had previously estimated reentry around 2034, but increased solar activity has caused the Earth’s atmosphere to swell, increasing atmospheric drag on the satellite [NASA].

What’s Next for Van Allen Probe B?

Van Allen Probe B is not expected to reenter Earth’s atmosphere until at least 2030, with a similar risk profile to its twin [USA Today].

Key Discoveries

The Van Allen Probes made several significant discoveries, including the identification of a transient third radiation belt that forms during periods of intense solar activity [NASA].

NASA and the Space Force will continue to monitor the reentry of Van Allen Probe A and provide updates as needed.