News: On May 11, NASA’s Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) spacecraft will depart asteroid Bennu, and start its two-year long journey back to Earth.
- OSIRIS-REx is NASA’s first mission to visit a near-Earth asteroid, survey its surface and collect a sample from it. The mission was launched in 2016, it reached its target in 2018 and since then, the spacecraft has been trying to match the velocity of the asteroid using small rocket thrusters.
- It also utilised this time to survey the surface and identify potential sites to take samples. In October 2020, the spacecraft briefly touched asteroid Bennu, from where it collected samples of dust and pebbles.
- Once the surface was disturbed, the spacecraft’s robotic arm captured some samples.
- The spacecraft’s engineers have also confirmed that shortly after the spacecraft made contact with the surface, it fired its thrusters and “safely backed away from Bennu”.
- Bennu is considered to be an ancient asteroid that has not gone through a lot of composition-altering change through billions of years, which means that below its surface lie chemicals and rocks from the birth of the solar system.
- Therefore, scientists and researchers are interested in studying this asteroid as it might give them clues about the origins of the solar system, the sun, the Earth and the other planets.
- So far, we know that Bennu is a B-type asteroid, implying that it contains significant amounts of carbon and various other minerals.
- Because of its high carbon content, the asteroid reflects about four per cent of the light that hits it, which is very low when compared with a planet like Venus, which reflects about 65 per cent of the light that hits it. Earth reflects about 30 per cent.