Why Bennu?

This animated feature takes a fun look at how asteroid Bennu was chosen as the target for the OSIRIS-REx mission. Starting in 2008, from a field of over 500,000 known asteroids, scientists went through a process to narrow the choices down to 5 final candidates. The selection criteria was based on an asteroid’s proximity to Earth, its orbit and size, and its chemical composition.
Bennu is a B-type asteroid with an approximately 500-meter diameter. It completes an orbit around the Sun every 436.604 days (1.2 years) and every 6 years it comes very close to Earth, within 0.002 AU. Bennu’s size, primitive composition, and potentially hazardous orbit make it one of the most fascinating and accessible near-Earth objects, and the ideal target for the OSIRIS-REx mission. For more details, visit the OSIRIS-REx website at asteroidmission.org.