The Bennu asteroid has captured the attention of astronomers for several reasons. Besides being pretty large (262.5 m in radius) and orbiting the Sun once every 437 days, the space rock is suspected to be harboring chemical elements that could favor life’s existence. NASA sent the OSIRIS-REx spacecraft there to clear any doubts, and we’re happy to see some results.
NASA released some images from a camera aimed at the spacecraft’s 11-foot-long robotic arm. Thanks to a sample collection device mounted at the end of the arm, a bottle of compressed nitrogen gas was fired as the spacecraft reached the surface of the asteroid.
The sample collection head is crammed with material gathered from the asteroid’s surface
After seeing close-up images of the sample collection head, scientists concluded that some asteroid particles were visible as they were escaping from the collection chamber.
The scientific team also gathered images with the navigation camera known as NavCam. The sequence begins an hour after OSIRIS-REx performed an orbit departure maneuver, and ends around two minutes after the spacecraft’s back-away burn. A rotation maneuver is visible in the middle of the image sequence when OSIRIS-REx points its sampling arm for target sampling site on the asteroid and in a region named “Nightingale.”
The OSIRIS-REx team wrote in a description of NavCam the following:
“As the spacecraft nears site Nightingale, the sampling arm’s shadow comes into view in the lower part of the frame. Shortly after, the sampling head impacts site Nightingale (just outside the camera’s field of view to the upper right) and fires a nitrogen gas bottle, which mobilizes a substantial amount of the sample site’s material,”
There’s an exciting mystery around, as the same team writes:
“Several seconds later, the spacecraft performs a back-away burn and the sampling arm’s shadow is visible against the disturbed surface material. The team continues to investigate what caused the extremely dark areas visible in the upper and middle parts of the frame,”
Bennu will remain in its place for a pretty long time, as it has no chance of colliding with Earth. In 2135, the asteroid will approach our planet at a distance of only 300,000 km, which means closer than the Moon.