One’s Trash is Another’s Treasure: Cosmic Rubble Piles

Until 15 years ago, meteorites and cosmic dust were the only extraterrestrial materials available for investigating the nature and chemical evolution of the early Solar System. Since then, three major sample return missions have significantly advanced our understanding of the material composing the small bodies that populate our Solar System. The asteroid sample return mission Hayabusa first proved the direct link between an asteroid type and the most common type of meteorites falling to Earth. The Hayabusa2 and OSIRIS-REx missions recently collected and returned material from two carbonaceous asteroids, Ryugu and Bennu, respectively. Together, the results from those samples are revealing information not gleaned from studies of meteorites and are revolutionizing our understanding of the formation and evolution of planetary bodies at the dawn of our Solar System.