A brown-and-white capsule that spent the last seven years swooping through the solar system and sojourning at an asteroid has finally come home. And it has brought a cosmic souvenir: a cache of space rock that scientists are hungry to get their hands on.

On Sunday morning, those scientists waited eagerly as the pod shot through Earth’s atmosphere at thousands of miles per hour. It gently parachuted down into the muddy landscape of the Utah Test and Training Range, about 80 miles west of Salt Lake City, at 8.52am local time.

The capsule’s landing is a major win for a Nasa mission called OSIRIS-REX, which stands for Origins, Spectral Interpretation, Resources Identification and Security-Regolith Explorer. The spacecraft set out in 2016 to retrieve material from Bennu, a carbon-rich asteroid about 190 feet wider than the height of the Empire State Building. Researchers hope this pristine space dirt will reveal clues about the birth of our solar system and the genesis of life on Earth.

“This is a gift to the world,” said Dante Lauretta, a planetary scientist at the University of Arizona and the principal investigator of the OSIRIS-REX mission, at a news conference last month.

Scientists who were working on the mission endured many twists and turns, including a seven-year struggle to get the project greenlit by Nasa. Their perseverance paid off as OSIRIS-REX became the first American spacecraft to retrieve material from an asteroid, bringing back a staggering amount of matter from space for scientists around the world to study. But the victorious final act means so much more for the OSIRIS-REX team members, many of whom “grew up on this mission”, according to Lauretta.

“A little bit of us is on that spacecraft,” said Rich Burns, the OSIRIS-REX programme manager at Nasa Goddard Space Flight Centre, at the news conference. “And a little bit of us is coming home with it.”

Bennu, a near-Earth asteroid, is currently many millions of miles from our planet. Like other asteroids in the solar system, it is a geological relic of the protoplanetary disk- a swirling mix of gas and dust that eventually coalesced into planets — that surrounded our sun billions of years ago. One theory is that small worlds like Bennu once seeded Earth with the prebiotic ingredients needed to form life.

But it is difficult to test this idea using meteorites, pieces of asteroids that reach Earth’s surface, which are heated by the atmosphere and are then contaminated by microbes on the ground, Lauretta said.

OSIRIS-REX’s delivery will provide an abundant new stock of space rock. The team anticipates about half a pound of unsullied asteroid dirt.

At 2am local time on Sunday morning, the OSIRIS-REX command team in Littleton, Colorado, evaluated the landing conditions and held a go-or-no-go poll on the capsule drop. The team voted go and OSIRIS-REX released the capsule at 4.42am.

Four hours later, it entered Earth’s atmosphere. The first parachute inflated 19 miles above the surface; a second was deployed just minutes later, slowing the cargo’s speed to 11 miles per hour.

New York Times News Service