Dr. Tra-Mi Ho (DLR Institute of Space Systems, Bremen)

The contributions of the Hayabusa Mission to our understanding of asteroids

The Japan Aerospace Exploration Agency (JAXA) launched its first near-Earth asteroid (NEA) sample return mission in May 2003: Hayabusa. The target of the mission was NEA Itokawa, an S-type asteroid with a size of about 330 m. Hayabusa reached Itokawa in September 2005 and performed a sample retrieval maneuver in November 2005. When the spacecraft returned in 2010 and brought the samples back to Earth, it was the world's first mission to return material from the surface of an asteroid to Earth. Based on the successful Hayabusa mission, JAXA launched its second sample return mission in December 2014, this time to C-Type asteroid, Ryugu. Ryugu is also an NEA with a size of about 1 km. Unlike the S-type Itokawa, which was expected to be composed of silicate material, Ryugu was supposed to contain carbonaceous material with hydrated minerals and possibly volatiles. Hayabusa2 returned its sample to Earth in December 2020. Although analysis of the sample has not yet been completed, this paper presents the preliminary results of the Hayabusa2 mission and the results of its predecessor Hayabusa mission.