Discovery of Preserved Presolar Silicate Grains in Ryugu Samples

Preserved presolar silicate grains have been discovered in surface samples collected from the Ryugu asteroid by the Hayabusa2 space probe. The unique fragments of rock, known as clasts, were found to have different chemical compositions compared to their surroundings and contained evidence of presolar grains. The presence of these grains suggests that they originated from another location in the solar system, possibly the Kuiper Belt, and somehow became embedded in the rubble field where Ryugu was located.