Samples returned from the asteroid Ryugu are similar to Ivuna-type carbonaceous meteorites

Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples of the C-type asteroid (162173) Ryugu were retrieved by the Hayabusa2 spacecraft. We measured the mineralogy and bulk chemical and isotopic compositions of Ryugu samples. The samples are mainly composed of materials similar to those of carbonaceous chondrite meteorites, particularly the CI (Ivuna-type) group. The samples consist predominantly of minerals formed in aqueous fluid on a parent planetesimal. The primary minerals were altered by fluids at a temperature of 37° ± 10°C, about [Formula: see text] million (statistical) or [Formula: see text] million (systematic) years after the formation of the first solids in…

• NA
  National Aeronautics and Space Administration
• CN
  Centre National d’Etudes Spatiales

  Award: Hayabusa2
• DZ
  Deutsches Zentrum für Luft- und Raumfahrt
• JA
  Japan Aerospace Exploration Agency