A United Launch Alliance Atlas V 411 configuration rocket launched the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) mission for NASA at 7:05 p.m. on 8 September 2016 from Space Launch Complex (SLC)-41 at Cape Canaveral Air Force Station, Florida.

Excerpts from the United Launch Alliance press release:
A United Launch Alliance (ULA) Atlas V 411 rocket will inject the OSIRIS-REx spacecraft into a hyperbolic trajectory away from Earth where it will begin a seven-year mission to return an asteroid sample.

The OSIRIS-REx mission will help scientists investigate the origins of our solar system, how water and organic material traveled to Earth, and increase understanding of asteroids that could impact Earth. In addition, the sample returned to Earth will further our understanding of water, organics and precious metals on asteroids, which could fuel future exploration missions.

Following separation, the OSIRIS-REx spacecraft will make precise maneuvers to modify its orbit around the sun to rendezvous, two years later, with the asteroid Bennu. Bennu, classified as a near-Earth asteroid, is roughly 0.3 miles in diameter and has an estimated mass of more than 65 million tons.

After arriving at Bennu, OSIRIS-REx will spend roughly two years scanning the chemical and physical properties of the asteroid. Laser ranging and optical instruments will map the surface to select its sample collection site. In 2020, OSIRIS-REx will approach Bennu and lightly touch the surface of the asteroid with a special boom-mounted instrument designed to collect material, or regolith, from the surface. The asteroid regolith will be stored in a sample return capsule for the two-year journey back to Earth, which will begin in 2021. As it approaches Earth, the spacecraft sample return capsule will separate from the main spacecraft and make a fiery plunge back to Earth for analysis, helping unlock the mysteries of our solar system’s formation.