Sep 17, 2016
Origins, Spectral Interpretation, Resource Identification, Security – Regolith Explorer (OSIRIS-REx) is first U.S. mission to sample an asteroid. Spacecraft was launched on Sept. 8, 2016, from Cape Canaveral Air Force Station in Florida.
Goals of the Mission:
- OSIRIS-REx will be conducting a range of scientific experiments in order to better understand the asteroid Bennu
- As part of this, the asteroid will be mapped using instruments on the probe, in order to select a suitable site for samples to be collected from.
- The aim of the mission is to collect a sample of regolith- the loose, soil-like material which covers the surface of the asteroid.
Why Bennu asteroid was chosen
Why was Bennu chosen?
- Nerness to Earth: In order for OSIRIS-REx to reach its destination in a reasonable timeframe, NASA needed to find an asteroid which had a similar orbit to Earth. Around 7000 asteroids are ‘Near-Earth Objects’ (NEOs), meaning they travel within around ~30million miles of the Earth. Out of these, just under 200 have orbits similar to Earth, with Bennu being one of these.
- Size: Small asteroids, those less than 200m in diameter, typically spin much faster than larger asteroids, meaning the regolith material can be ejected into space. Bennu is around 500m in diameter, so rotates slowly enough to ensure that the regolith stays on its surface
- Composition: Bennu is a primitive asteroid, meaning it hasn’t significantly changed since the beginning of the Solar System. This asteroids is expected to host in varying degree: Organic molecules — those made from carbon — and molecules like water are considered key ingredients for life to evolve.