The capsule, which fell back to Earth on September 24 with fragments of an asteroid on board, may have made the most visited atmosphere re-entry in history.
This capsule, released by the American probe Osiris-REx, was expected because of its extremely rare content: the space probe had touched the asteroid Bennu three years ago. Until then, only two Japanese probes had returned asteroid fragments to Earth in 2010 and 2020.
Predictable return to school
But Osiris-REx (short for Origins-Spectral Interpretation Resource Identification Security Regolith Explorer) was also expected for an equally rare opportunity. Its capsule represented a “cosmic” object that could predict the exact time of its re-entry into the atmosphere and whose trajectory and speed were comparable to those of a meteorite.
However, little data is available about the behavior of meteorites in our atmosphere, and for good reason because we are rarely able to observe them live.
The most we can do is measure the energy behind an explosion. Like the 18 meter meteorite that exploded over Chelyabinsk, Russia in 2013.
Since this explosion had a force more than 30 times greater than that of the Hiroshima atomic bomb, experts in the field had good reason to demand that we follow the capsule’s re-entry second by second.