"OSIRIS-REx: Revolutionizing Our Understanding of Asteroids"

NASA's OSIRIS-REx spacecraft, the third mission to collect a sample from an asteroid, provided new insights into the nature of asteroids. The mission revealed that many asteroids are not solid blocks of rock but conglomerations of boulders, sand, and gravel held together by weak gravitational forces. OSIRIS-REx's target asteroid, Bennu, surprised scientists with its porous and oddly structured rocks, which act as a crumple zone, absorbing the energy of impacts and protecting the asteroid's surface. The spacecraft's touchdown on Bennu also revealed that the surface layer of the asteroid has a much lower density than the rest of the body, suggesting the presence of empty spaces between rocks. The analysis of the sample collected by OSIRIS-REx may provide further insights into the asteroid's collisional history.