Research led by CU Boulder is revealing the Alice in Wonderland-like physics that govern gravity near the surface of the asteroid Bennu. Consequently, NASA's OSIRIS-REx mission - one of the most ambitious space missions ever attempted - is studying the distant asteroid to unlock its secrets.
If everything goes according to plan, the probe will spend the next two years studying Bennu, then secure a sample from the surface before heading back to Earth in March 2021.
"The discovery of [the] plumes is one of the biggest surprises of my scientific career", said principal investigator Dante Lauretta of the University of Arizona.
Also, the camera on the spacecraft discovered particle plumes erupting from the Bennu surface.
"Bennu is really teasing us", said Dante Lauretta, the principal investigator for the spacecraft, which is now orbiting the asteroid.
Bennu has been an exciting learning experience for NASA that drives home how little we know about asteroids.
Shortly after the discovery of the particle plumes on January 6, the mission science team increased the frequency of observations, and subsequently detected additional particle plumes during the following two months.
The mission's scientists shared pictures of the plumes as well as the unexpectedly rugged terrain on the asteroid, known as Bennu, today at the Lunar and Planetary Science Conference in The Woodlands, Texas. But the abundance of large boulders meant the teams will need much better aim to safely touch down and collect the material they hope to bring home to Earth.
Scientists are evaluating the asteroid in search of a suitable landing site for the spacecraft's sample collection mission, but one hasn't been identified at this time. Dozens to hundreds of particles, from pebbles up to fist-sized rocks, were flying at high speeds off of Bennu's surface.
The team also says they found more boulders at the surface than expected.
Some the particles continue out into interplanetary space, some go into orbit around Bennu, and some rain down on the surface.
They've recently made some interesting discoveries that could give us clues to the origins of earth's water and potential life in other solar systems. Samples from the asteroid, which are expected back on earth by 2023, will help us answer some of the biggest questions about where we come from, according to an official press release.
To study those forces, Scheeres and his colleagues use OSIRIS-REx's navigational instruments to measure the minute tug that the asteroid exerts on the spacecraft.
The greatest surprise of the mission happened only a few days in and an unexpected observation occurred signaling activity on Bennu, the researchers said.
When the mission was planned, scientists were aiming to take dirt and gravel from an area measuring at least 50 metres in diameter that was free of boulders or steep slopes, which would pose a hazard. "Bennu has issued us a challenge to deal with its rugged terrain, and we are confident that OSIRIS-REx is up to the task".
As a result, Bennu's rotation period is decreasing by about a second every 100 years, the scientists explained. OSIRIS-REx is the third mission in NASA's New Frontiers Program, which is managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for the agency's Science Mission Directorate in Washington.