NASA's first asteroid samples brought back from deep space parachuted into the Utah desert on September 24, ending their seven-year journey, Euronews reported.
During a flyby over Earth, the Osiris-Rex spacecraft released the sample capsule from an altitude of 100,000 km. The small capsule landed four hours later on a remote military site while the mother ship headed for another asteroid.
Scientists believe the capsule contains at least a cup (or about 235 ml) of debris from the carbon-rich asteroid known as Bennu, but they won't know for sure until the container is opened.
Some of the debris is said to have scattered and floated away when the spacecraft scooped up too much of it, and rocks jammed the lid of the container during collection three years ago.
Japan, the only other country to bring back asteroid samples, collected about a teaspoon on a pair of asteroid missions for comparison.
The pebbles and dust delivered today represent the largest haul ever from the far side of the Moon. The samples are believed to be preserved building blocks from the dawn of the solar system 4.5 billion years ago and will help scientists better understand how Earth and life formed on it.
The Osiris-Rex mothership set off on a €937 million mission in 2016. It reached Bennu two years later and, using a long-stick vacuum, scooped up debris from the small rounded space rock in 2020. Until it returns the spacecraft had orbited a staggering 6.2 billion kilometers.
NASA's recovery efforts in Utah included helicopters, as well as a temporary clean room set up at the Department of Defense Utah Proving Ground for testing and training.
The samples will be taken on September 26 to a new laboratory at NASA's Johnson Space Center in Houston. The building now houses the hundreds of kilograms of moon rocks collected by the Apollo astronauts more than half a century ago.
Mission lead scientist Dante Lauretta of the University of Arizona will accompany the samples to Texas. Opening the container in Houston in the next day or two will be "the real moment of truth" given the uncertainty about the amount inside, he said before landing.
Engineers estimate that the container contains 250 grams of Bennu material, plus or minus 100 grams. Even in the pessimistic scenario, she would easily exceed the minimum mission requirement, Lauretta confirmed.
It will likely take several weeks to get an accurate measurement, NASA says, but plans to publicly present and display the results in October.
Bennu currently orbits the Sun 81 million kilometers from Earth and is about half a kilometer in diameter, about the size of the Empire State Building - but in the shape of a spinning top. It is believed to be a broken off fragment of a much larger asteroid.
During the two-year survey, Osiris-Rex found Bennu to be a crumbling pile of debris, full of boulders and craters.
The surface was so loose that the spacecraft's vacuum arm sank about 0.5 meters into the asteroid, sucking up more material than intended—hence the lid jam.
These close-up observations may prove useful at the end of the next century. Bennu is expected to come dangerously close to Earth in 2182 - possibly close enough to impact.
The data collected by "Osiris-Rex" will help in any effort to deflect an asteroid, according to Dante Lauretta./BGNES