About seven in the evening on a quiet September working day in 2016 an Atlas V rocket growled its way into room from Cape Canaveral. On board was NASA’s OSIRIS-Rex mission to research the carbonaceous asteroid recognized as “Bennu” and to deliver back again some sixty grams of substance for research on Earth.
Some four many years later on, owning arrived at Bennu in December 2018, the mission is now in a prolonged preparing time period for that oh-so-treasured seize at a small piece of this rubbly, seventy-million ton repository of pristine substance from the earliest days of our forming solar system. A essential aspect of that preparing is making sure 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 once more.
On April 14th 2020 the spacecraft produced a preparatory descent, dropping to about sixty five meters over Bennu’s surface area and then retreating, all completed in about ten minutes. Under is a great time lapse of photographs taken by OSIRIS-REx. The most significant boulder at the level of lowest descent is about 13 meters across. Also at that level you can just see the smoother, darker patch (recognized as sample web-site Nightingale) that will be the eventual touchdown focus on.
In August 2020 the strategy is to descend all the way to the surface area to deploy the ‘Touch-and-Go’ sampling arm (noticed in the heart of the over photographs). This product incorporates a system to swiftly blast the surface area with nitrogen gas to loft substance into the sampling head to test to get chunks up to a couple of centimeters across. Meanwhile lesser dust particles will get passively gathered on pads produced of finely looped stainless steel.
OSIRIS-REx can make 3 such tries if essential. Once adequate of a sample has been captured it will seal it up, and – with a minimal luck and a lot of engineering – deliver that sample back again to Earth in September 2023, dropping onto a US Airforce assortment in Utah on the finish of a parachute.
But in addition to the scientific insights to our solar system’s heritage there is a fairly much more sobering drive for visiting Bennu. In the rankings of asteroids that are prospective hazards for the Earth – with orbits that cross our have – Bennu is range two in a cumulative system of assessment that includes the prospective impact power yield.
In actuality the estimate is that Bennu has a 1-in-2700 prospect of hitting the Earth sometime amongst 2175 and 2199. Although that is much from worry-inducing, Bennu’s rubbly character and exercise (from time to time spurting out dust and rocks, possible thanks to thermal variations and volatiles) indicate that its orbit might practical experience a selected total of random shifting more than time, in addition to variations from the Yarkovsky impact. OSIRIS-REx’s info will enable refine our photograph of Bennu’s long term threat, on the other hand not likely.