Bennu, the asteroid, is the target of the NASA's OSIRIS-REx mission which is intended to return its samples to Earth in 2023 for further study. On 3 December 2018, the OSIRIS-REx spacecraft arrived at Bennu after a two-year journey. Here's what you need to know about it.
NASA’s Osiris-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) space probe made history on October 28, 2020, when it ‘kissed’ the surface of asteroid Bennu. The probe is designed to collect samples of the asteroid’s surface and return the pieces to earth. While you are it, read about ‘Blanets‘ as well.
OSIRIS-REx was launched on September 8, 2016, and it reached the proximity of the asteroid named ‘Bennu’ on December 3, 2018. It began investigating the asteroid’s surface to locate a suitable place for collecting the sample from it.
NASA’s Goddard Space Flight Center controlled the project’s overall management, engineering, and navigation. The principal science operations are managed by the University of Arizona’s Lunar and Planetary Laboratory, and the spacecraft for mission operations is provided by Lockheed Martin Space Systems. The mission’s cost is approximated to be around $800 million, excluding the value of Atlas V launch vehicle, which costs about $183.5 million.
Bennu- The Time Capsule
Bennu, the asteroid, is located about 330 million kilometers away from earth. Scientific research has shown that Bennu was most likely born within the first 10 million years of the solar system formation and had probably remained undisturbed for close to 4.5 million years.
The asteroid has a very dark-colored surface. It is classified as a B-type asteroid, considered “primitive,” i.e., these asteroids are believed to have undergone little geological change from their formation time.
Pristine carbonaceous material, a key element in organic molecules necessary for life and representative of matter from before earth’s formation, is found on Bennu.
Thus, Bennu is also regarded as a time capsule for us because it has preserved the universe’s chemical constituency from its formative years. Samples from the asteroid can help us understand our planet’s origins and that of the solar system.
The Touchdown on Bennu
The OSIRIS-Rex space probe was launched on September 8, 2016, from Cape Canaveral Air Force Station. After a journey of over four years, OSIRIS-REx touched the surface of asteroid Bennu in October 2020.
The probe used its 8-meter diametric robotic arm and fired pressurized nitrogen to agitate the surface material for collecting samples from the asteroid. This technology is called the Touch-and-Go Sample Acquisition Mechanism (TAGSAM). The space probe comprises a long boom with a ring-shaped collection chamber on end, which spouts a squirt of nitrogen on the asteroid’s surface, leading to rocky pieces getting trapped inside the probe’s collection chamber.
With a period of contact of just six seconds with the asteroid, when Osiris-REx comes back to earth, it will have the most significant chunk of space rocks ever collected since the Apollo lunar missions. The mission’s primary goal is to collect a sample of at least 60 g.
If the space probe has collected the required sample, it will begin a long journey back to earth, with a pre-planned landing in the Utah desert, estimated in September 2023.
“NASA’s team put the probe in just the right place- almost near the center of the targeted sampling zone”, told Rich Burns, NASA’s project manager for the mission.
If successful, OSIRIS-REX will be the latest success after Japan’s Hayabusa2 space probe which collected samples from asteroid Ryugu in 2019 and is now on its way home. The first Japanese Hayabusa probe returned samples from asteroid 25143 Itokawa in 2010.
The United States will join the highly exclusive list of “asteroid rock catchers” if it is successful in the mission. Until then, the world awaits the triumphant return of OSIRIS-REx.