Bennu, an ancient and rocky near-Earth asteroid about 550 yards (about 500 meters) wide. Asteroids like Bennu are made of material from the earliest days of the solar system. When NASA’s OSIRIS-REx spacecraft arrived at asteroid Bennu in December 2018, its close-up images confirmed what mission planners had predicted nearly two decades before: Bennu is made of loose material weakly clumped together by gravity, and shaped like a spinning top. This major validation, however, was accompanied by a m