This is the first time scientists have had close-up observations of particle plumes erupting from an asteroid's surface, the agency said. "A few of these gradual-transferring particles have been noticed over intervals of a minimum of every week, and they look like trapped within the asteroid's gravity discipline and are ending up in orbit round Bennu", he stated. If you were standing inside the boundaries of Bennu's Roche lobe and slipped on a banana peel, for example, not much would happen-you'd be captured by the lobe and fall back to the surface.
NASA has concluded the particle clouds don't pose a danger to the spacecraft, giving OSIRIS-REx the all-clear to move in and investigate.
Lauretta stated the plume discovery at Bennu was one of many most massive surprises of his scientific profession. "Bennu is already surprising us, and our exciting journey there is just getting started", Lauretta said.
OSIRIS-REx will now have to be flown to a smaller area where boulders are less concentrated.
Scientists say the ancient asteroid could hold clues to the origin of life. Bennu is essentially a leftover from the formation of our solar system billions of years ago, although some of the minerals inside it could be even older.
"It is not trivial to deliver a spacecraft with meter scale resolution to the surface of an asteroid in the microgravity environment", said Lauretta, who nevertheless said he was "confident" that the team would rise to the challenge. Interestingly, while it is not known for sure what is causing the ejection events, NASA has noticed they have occurred around the time of Bennu's closest passage to the sun during the asteroid's elliptical orbit. Hayabusa2 arrived at Ryugu last summer and also discovered a surface strewn with boulders. Although, some remained in orbit of the asteroid.
Based on terrestrial observations, NASA's OSIRIS-REx team expected to find a relatively smooth orb, with maybe a few large boulders. Instead, it's rough and crowded with boulders.
An artist's concept of the OSIRIS-REx's sample collection instrument, TAGSAM.
This mosaic image of the asteroid Bennu is composed of 12 PolyCam images collected by the OSIRIS-REx spacecraft from 15 miles away.
The asteroid, 490 metres wide and shaped like a diamond, is ejecting an unknown substance into space, scientists said.
Early results from Japan's Hayabusa 2 space mission orbiting the asteroid Ryugu also released on Tuesday.
"This is what discovery is all about - surprises, quick thinking and doing what it takes to get good science", said Lori Glaze, acting director of NASA's planetary-science division. Bennu may contain compounds or traces that have survived since the birth of our solar system. OSIRIS-Rex's sample will help us answer some of the biggest questions about where we come from'. At least, that's what NASA scientists thought.
Bennu is the target of NASA's Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) mission, which began orbiting the asteroid on December 31 previous year.
The spacecraft launched on September 8, 2016 at 19:05 EST aboard an Atlas V rocket. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft.
As OSIRIS-REx surveys asteroid Bennu in detail, the mission team is beginning to identify potential locations for the spacecraft to collect a sample.
Separate research recently found that the asteroid's rotation is speeding up.