After nearly two years circling an historic asteroid lots of of thousands and thousands of miles away, a Nasa spacecraft will this week try and descend to the treacherous, boulder-packed floor and snatch a handful of rubble.
The drama will unfold on Tuesday because the US has its first go at accumulating asteroid samples for return to Earth, a feat achieved solely by Japan up to now.
The Osiris-Rex mission is trying to carry again at the least two ounces (60 grams) value of asteroid Bennu, the largest such haul from past the moon.
The van-sized spacecraft is aiming for the comparatively flat center of a tennis court-sized crater named Nightingale — a spot comparable to some parking locations right here on Earth. Boulders as large as buildings loom over the focused landing zone.
“So for some perspective, the following time you park your automotive in entrance of your own home or in entrance of a espresso store and stroll inside, take into consideration the problem of navigating Osiris-Rex into certainly one of these spots from 200 million miles away,” Nasa’s deputy venture supervisor Mike Moreau stated.
As soon as it drops out of its half-mile-high (0.75 km-high) orbit round Bennu, the spacecraft will take a deliberate 4 hours to make all of it the best way down, to simply above the floor.
Then the motion cranks up when Osiris-Rex’s 11-foot (3.4-metre) arm reaches out and touches Bennu.
Contact ought to final 5 to 10 seconds, simply lengthy sufficient to shoot out pressurised nitrogen fuel and suck up the churned grime and gravel.
Programmed prematurely, the spacecraft will function autonomously in the course of the unprecedented touch-and-go manoeuvre. With an 18-minute lag in radio communication every approach, floor controllers for spacecraft builder Lockheed Martin close to Denver can not intervene.
If the primary try doesn’t work, Osiris-Rex can strive once more. Any collected samples is not going to attain Earth till 2023.
Whereas Nasa has introduced again comet mud and photo voltaic wind particles, it has by no means tried to pattern one of many practically a million recognized asteroids lurking in our photo voltaic system till now.
Japan, in the meantime, expects to get samples from asteroid Ryugu in December — within the milligrams at most — 10 years after bringing again specks from asteroid Itokawa.
Bennu is an asteroid picker’s paradise. The massive, black, roundish, carbon-rich house rock — taller than New York’s Empire State Constructing — was round when our photo voltaic system was forming 4.5 billion years in the past.
Scientists think about it a time capsule filled with pristine constructing blocks that might assist clarify how life fashioned on Earth and probably elsewhere.
The mission’s principal scientist, Dante Lauretta of the College of Arizona, stated: “That is all about understanding our origins.”