It’s only 5.4 grams, but it weighs too much for planetary science. Japanese research teams, in collaboration with international experts, have analyzed rock samples from an asteroid, one of the oldest and most ancient objects in the Solar System. The results, now published in two papers in the journal “Nature Astronomy,” provide important pieces of the puzzle for the effort to put together a picture of the origins of the Solar System.
The samples were taken with the Hayabusa-2 spacecraft in 2019 directly from the asteroid Ryugu and sealed well to Earth in 2020. Ryugu is about a kilometer long and as black as coal. Its rock is likely to consist of the material from which the Sun and the planets arose about 4.5 billion years ago, but unlike these, Ryugu has been practically unchanged since then in the form of a geochemical freezer traversing our solar neighborhood. Accurate microscopic, chemical and mineralogical analyzes can reveal more about the conditions under which the Solar System was formed.
© JAXA (detail)
Japanese asteroid probe Hayabusa-2 | On February 21, 2019, Japanese space probe Hayabusa-2 with its horn-like sample collector touched for a few seconds the surface of asteroid Ryugu, which is about a meter tall. He fired a ball of tantalum through the horn to detonate and capture the material from the asteroid.
The first results of such studies are now available. The work that has now been published aims to provide a rough overview of the material brought into the Hayabusa-2 capsule. so saves first publication Toru Yada’s team from the Japanese space agency JAXA compiled a list of the fragments and their appearance.
airy mix of millimeter-sized pieces
The coarsest grains measure just under eight millimeters, while the finer dust extends into the sub-millimeter range. The material comes from the surface of the asteroid, which has been exposed to radiation and other impacts from space for millions of years, and from a small artificial crater that the space probe deliberately hit. At least a little bit of it, so hope, must come from deep, protected and thus exclusively native regions.
