The Japan Aerospace Exploration Agency (JAXA) announced on February 2 that it was found that moisture is not contained in the rocks on the surface at the asteroid "Ryugu" which the explorer "Hayabusa 2" is investigating. Many carbon-rich "C type asteroids" like ryugu were known to contain moisture in rocks, and were expected to have all the materials of life. It is unclear whether the ryugu was originally free from moisture or evaporated by sunlight.
According to team Hirohe Kitato Hiroshi Aizu, professor Aizu examined approximately 54,000 surfaces on the surface since the end of June when Hayabusa 2 arrived in Ryugu, but data indicating that there is rock containing moisture is obtained There was not. Ryuguu is far away from the earth, and sufficient data has not been obtained even with ground observation so far.
Hayabusa 2 decides the landing point during this month and plans to land for the first time in autumn. Kitasato said, "There is a possibility that moisture will be found when making artificial craters on the surface of Ryugu next spring." (Shotaro Hamada)