Tickling the Asteroid’s Tail – Scientific American Blog Network

All around seven in the evening on a quiet September working day in 2016 an Atlas V rocket growled its way into house from Cape Canaveral. On board was NASA’s OSIRIS-Rex mission to research the carbonaceous asteroid known as “Bennu” and to convey back some sixty grams of product for research on Earth. 

Some 4 several years later, possessing arrived at Bennu in December 2018, the mission is now in a lengthy planning period for that oh-so-valuable seize at a very small piece of this rubbly, seventy-million ton repository of pristine product from the earliest days of our forming photo voltaic program. A important aspect of that planning is generating positive the spacecraft can be safely and securely maneuvered down to the asteroid’s surface area, to a predetermined sampling zone, and be safely and securely maneuvered away again. 

On April 14th 2020 the spacecraft created a preparatory descent, dropping to about sixty five meters earlier mentioned Bennu’s surface area and then retreating, all completed in about ten minutes. Down below is a superb time lapse of pictures taken by OSIRIS-REx. The greatest boulder at the position of cheapest descent is about 13 meters across. Also at that position you can just see the smoother, darker patch (known as sample web-site Nightingale) that will be the eventual landing target.

Credit score: NASA, Goddard and University of Arizona

In August 2020 the prepare is to descend all the way to the surface area to deploy the ‘Touch-and-Go’ sampling arm (observed in the middle of the earlier mentioned pictures). This system incorporates a program to rapidly blast the surface area with nitrogen gasoline to loft product into the sampling head to consider to get chunks up to a pair of centimeters across. Meanwhile more compact dust particles will get passively gathered on pads created of finely looped stainless metal. 

OSIRIS-REx can make a few these types of attempts if needed. When more than enough of a sample has been captured it will seal it up, and – with a minimal luck and a whole lot of engineering – convey that sample back to Earth in September 2023, dropping on to a US Airforce selection in Utah on the finish of a parachute. 

But in addition to the scientific insights to our photo voltaic system’s record there is a considerably much more sobering determination for viewing Bennu. In the rankings of asteroids that are potential dangers for the Earth – with orbits that cross our very own – Bennu is amount 2 in a cumulative program of evaluation that consists of the potential effects electrical power generate.

In simple fact the estimate is that Bennu has a one-in-2700 prospect of hitting the Earth someday concerning 2175 and 2199. Though that is far from worry-inducing, Bennu’s rubbly nature and exercise (at times spurting out dust and rocks, very likely thanks to thermal improvements and volatiles) necessarily mean that its orbit might working experience a sure sum of random shifting about time, in addition to improvements from the Yarkovsky outcome. OSIRIS-REx’s knowledge will aid refine our image of Bennu’s upcoming threat, nevertheless unlikely.