Bennu is a roughly 0.3-mile-wide (500 meters) asteroid that orbits in near-Earth space. Scientists suspect it's a chunk of a larger asteroid that broke off due to a collision farther out. Telescope observations and data collected by NASA's OSIRIS-REx spacecraft showed that Bennu has minerals that have been altered by water. Hence, scientists suspect the asteroid's parent body accreted ice that subsequently melted after it formed around 4.5 billion years ago...The team found various varieties of the aqueously altered minerals, including serpentine, smectite, carbonates, magnetite, sulfides, and phosphates. The minerals are present as individual particles and as crusts coating other...