Extract from ABC News
A NASA space capsule carrying the largest soil samples ever scooped up from the surface of an asteroid has streaked through Earth's atmosphere and parachuted into the Utah desert.
Key points:
- Bennu is expected to come dangerously close to Earth in 2182
- Scientist says data gleaned by Osiris-Rex will help with any asteroid-deflection effort
- The samples represent the biggest haul from beyond the moon
In a flyby of Earth, the Osiris-Rex spacecraft released the sample capsule from 100,000 kilometres out.
The small capsule landed 4 hours later on a remote expanse of military land, as the mothership set off after another asteroid.
"We have touchdown!" Flight Control announced, immediately repeating the news, since the landing occurred 3 minutes before anticipated.
Officials later said the orange-striped parachute opened four times higher than anticipated — around 6,100 metres — which led to the early touchdown.
The recovery team confirmed that the capsule was intact and had not been breached.
"This sample return is really historic," NASA scientist Amy Simon told AFP.
"This is going to be the biggest sample we've brought back since the Apollo moon rocks" were returned to Earth, she said.
Scientists estimate the capsule holds at least a cup of rubble from the carbon-rich asteroid known as Bennu, but will not know for sure until the container is opened.
NASA Administrator Bill Nelson said the samples will provide “an extraordinary glimpse into the beginnings of our solar system".
With these samples, "we are edging closer to understanding its early chemical composition, the formation of water, and the molecules life is based on," astronomer Daniel Brown of Nottingham Trent University in England said.
Some spilled and floated away when the spacecraft scooped up too much and rocks jammed the container's lid during collection three years ago.
Currently orbiting the sun 81 million kilometres from Earth, Bennu is about one-half of a kilometre across, roughly the size of the Empire State Building but shaped like a spinning top.
It is believed to be the broken fragment of a much larger asteroid.
The space rock is classified as a "near-Earth object" because it passes relatively close to our planet every six years.
Bennu is expected to come dangerously close to Earth in 2182 — possibly close enough to hit.
The data gleaned by Osiris-Rex will help with any asteroid-deflection effort, according to Dante Lauretta, the mission's lead scientist.
The pebbles and dust delivered on Sunday represent the biggest haul from beyond the moon.
Osiris-Rex, the mothership, rocketed away on the $US1 billion ($1.55 billion) mission in 2016.
It reached Bennu two years later and, using a long stick vacuum, grabbed rubble from the small roundish space rock in 2020.
By the time it returned, the spacecraft had logged 6.2 billion kilometres.
Next phase
NASA's recovery effort in Utah included helicopters as well as a temporary clean room set up at the Defence Department's Utah Test and Training Range.
The samples will be flown on Monday morning to a new lab at NASA's Johnson Space Center in Houston.
The building already houses the hundreds of kilograms of moon rocks gathered by the Apollo astronauts more than a half-century ago.
The mission's lead scientist, Dante Lauretta of the University of Arizona, will accompany the samples to Texas.
The opening of the container in Houston in the next day or two will be "the real moment of truth", given the uncertainty over the amount inside, he said ahead of the landing.
Engineers estimate the canister holds 250 grams of material from Bennu.
Even at the low end, it will easily surpass the minimum requirement of the mission, Mr Lauretta said.
It will take a few weeks to get a precise measurement, said NASA's lead curator Nicole Lunning.
NASA plans a public show-and-tell in October.
Preserved building blocks from the dawn of our solar system 4.5 billion years ago, the samples will help scientists better understand how Earth and life formed.
Japan, the only other country to bring back asteroid samples, gathered about a teaspoon in a pair of asteroid missions.
AP
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