The new year is off to a very impressive start in space science:
** OSIRIS REx successfully orbited Bennu, the smallest body ever orbited by a spacecraft. (See posting here) – NASA’s OSIRIS-REx Spacecraft Enters Close Orbit Around Bennu, Breaking Record – OSIRIS-REx Mission
Now, the spacecraft will circle Bennu about a mile (1.75 kilometers) from its center, closer than any other spacecraft has come to its celestial object of study. (Previously the closest orbit of a planetary body was in May 2016, when the Rosetta spacecraft orbited about four miles (seven kilometers) from the center of the comet 67P/Churyumov-Gerasimenko.) The comfortable distance is necessary to keep the spacecraft locked to Bennu, which has a gravity force only 5-millionths as strong as Earth’s. The spacecraft is scheduled to orbit Bennu through mid-February at a leisurely 62 hours per orbit.
Now that the OSIRIS-REx spacecraft is closer to Bennu, physical details about the asteroid will leap into sharper focus, and the spacecraft’s tour of this rubble pile of primordial debris will become increasingly detailed and focused.
In 2020, OSIRIS-REx will come down onto the surface of Bennu and grab a sample of regolith. The sample will be returned to Earth in 2023.
** New Horizons flew past Ultima Thule, the most distant object ever targeted by a space mission. (See posting here.) New Ultima Thule Discoveries from NASA’s New Horizons – New Horizons. Here is a press briefing held on Thursday:
Scott Manley reviews the three heroic missions: