Tonight at 9 p.m. KST, Hitoshi Kuninaka, of the Japan Aerospace Exploration Agency (JAXA), will give live the first news of the dust collection carried out by Hayabusa 2 on the asteroid Ryugu in 2019. The precious cargo, placed in a 40 cm capsule, had been dropped on Earth by the probe during its passage at 220,000 km, on December 5, 2020. It had finished its course at the end of a parachute in the Australian desert. Recovered by helicopter, it was transported to Japan, to the Institute of Space and Astronautical Sciences (ISAS), about a week ago.
Grains older than the Sun itself
What is the exact amount of asteroid dust collected by the probe between February and July 2019? What is the nature of the gas trapped at the time of harvest? Here is probably the first information that JAXA should deliver. It is indeed far too early for further analyzes of this dust, which is assumed to contain grains older than the Sun itself (4.6 billion years). The asteroid Ryugu, about a kilometer wide, is indeed the fragment of a larger body that formed very early on, probably during the collapse of the protosolar cloud that gave birth to the solar system.
A very long-term study program
As a first step, a catalog of all the grains will be produced in Japan. Laboratories around the world will then be able to benefit from these samples for analysis, after validation of their request by a committee of international experts. Finally, a large part, perhaps half it will depend on the total amount of dust collected, will be kept for at least 10 years in order to be analyzed in the future with more efficient tools, and possibly to answer questions that may arise. ‘we don’t ask ourselves yet. There is only one certainty: it is a very long study program which will begin this evening …