For those attracted by apocalyptic scenarios, errant asteroids are always a possibility. Several have orbits that take them near earth (in astronomical terms), and as the orbits can change due to factors such as gravity and surface temperature, they merit close observation. As part of this endeavor, NASA recently launched its OSIRIS REx probe towards Bennu, known more formally in the astronomy trade as 101955 Bennu, a body that is expected to have several close encounters with earth in the late 22nd century. The probe will arrive at its destination in 2019 and begin a detailed study of it properties, composition and orbit. It will conclude by taking samples from the body’s surface and return them to earth in 2023.
Apart from self-preservation for us earthlings, the mission is intriguing from a purely scientific point of view. Asteroids are left over from the formation of the solar system some four billion years ago, and are composed of its primary building blocks. If successful, the mission will expand our understanding of the origins and nature of our celestial neighborhood.