A re-entry of a NASA satellite would exceed the agency’s own risk guidelines

No one on Earth has been injured by falling space debris, but there are examples of space debris causes material damage.

NASA’s two Van Allen probes were launched into elliptical orbits that varied from a few hundred miles above Earth to an apogee, or high point of about 20,000 miles. Orbits are inclined 10 degrees to the equator, limiting the risk of injury or damage to part of the tropics. NASA ended the mission in 2019 when the satellites ran out of fuel.

At the time, NASA engineers expected the spacecraft to re-enter the atmosphere in 2034. But the higher-than-expected solar activity caused the atmosphere to swell outward, increasing the atmospheric drag on the satellites more than originally estimated, according to NASA. Van Allen Probe B is expected to re-enter no later than 2030, with a similar risk to the public.

The two spacecraft were developed by Johns Hopkins University’s Applied Physics Laboratory. NASA said the mission made a number of major discoveries, including “the first data indicating the existence of a transient third radiation belt that can form during intense solar activity.”

Several NASA satellites have re-entered the atmosphere without meeting the government’s risk standard. One of the satellites, the Rossi X-ray Timing Explorer, was de-orbited in 2018 and had a 1 in 1,000 chance of harming someone on the ground. No one was injured. RXTE was launched in 1995. just four months ago NASA released its first standard for orbital debris mitigation and reentry risk management.

While NASA has previously exceeded its standards, the US government is not the primary offender when it comes to unmitigated re-entry risks. China launched four heavy-lift Long March 5B missiles between 2020 and 2022 and left the massive main stages In orbit to return to Earth. Four abandoned rocket cores, each weighing about 24 tons, re-entered the atmosphere uncontrolled. Two of them – in Ivory Coast and Borneo – dumped debris on land, but no injuries were reported.