OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) is a NASA asteroid study spacecraft. It’s mission is to collect at least 60 grams of material from the near-earth asteroid 101955 Bennu and return it to Earth.
OSIRIS-REx was the third planetary science mission selected in the New Frontiers program, after Juno and New Horizons and was launched aboard the United Launch Alliance Atlas V 411 from Cape Canaveral, Space Launch Complex 41 on September 8, 2106.
Osiris-REx is 7 foot 10 inches in length, 7 foot 10 inches wide and 10. 3 feet tall. With the solar arrays deployed it is 20.2 feet wide and they generate 1226 to 3000 watts, stored in Li-Ion batteries, depending on its distance from the Sun. The propulsion system is hydrazine monopropellant, developed for the Mars Reconnaissance Orbiter. The sample will return to Earth via a parachute assisted landing, September 24, 2023, at the Air Force’s Utah Test and Training Range.
Bennu was chosen because it is believed to be a time capsule of the birth of the solar system. It is considered to be primitive, having changed very little since its formation. The sample was taken October 28, 2020 and the OSIRIS-REx completed its final flyover of Bennu and started drifting away from the asteroid and headed home.
What OSIRIS-REx stands for and science objectives – From the NASA Website
O – Origins
Return and analyze a sample of a pristine carbon-rich asteroid to study the nature, history, and distribution of its minerals and organic material.
SI – Spectral Interpretation
Define the global properties of a primitive carbon-rich asteroid to allow for direct comparison with existing ground-based telescopic data for all asteroids.
RI – Resource Identification
Map the global properties, chemistry, mineralogy of a primitive carbon-rich asteroid to define its geologic and dynamic history and provide context for the returned sample.
S – Security
Measure the Yarkovsky Effect on Bennu and learn which asteroid properties contribute to this effect.
The Yarkovsky Effect is the force caused by the emission of heat from a rotating asteroid that can change its orbit over time.
REx – Regolith Explorer
Document the texture, morphology, geochemistry, and spectral properties of the regolith (surface material) at the sampling site.