Reentry of NASA satellite will exceed the agency's own risk guidelines
A NASA satellite that spent more than a decade coursing through the Van Allen radiation belts encircling Earth is about to fall back into the atmosphere.
Most of the spacecraft will burn up during reentry, but a fraction of the material making up the 1,323-pound (600-kilogram) satellite will likely reach Earth's surface without vaporizing in the atmosphere. Uncontrolled reentries of satellites with comparable mass happen quite regularly-multiple times per month, according to one recent study-but most of them are older spacecraft or spent rocket bodies.
This reentry is notable because it poses a higher risk to the public than the US government typically allows. The risk of harm coming to anyone on Earth is still low, approximately 1 in 4,200, but it exceeds the government standard of a 1 in 10,000 chance of an uncontrolled reentry causing a casualty.