A NASA spacecraft has successfully landed on an asteroid, collecting a handful of space rubble to bring back to Earth in a daringly delicate operation.
“I can’t believe we actually pulled this off,” lead scientist Dante Lauretta, of the University of Arizona, said after Wednesday’s landing.
“The spacecraft did everything it was supposed to do.”
The mission team erupted into cheers when the Osiris-Rex spacecraft sent back confirmation that it had made contact with the 510-metre-wide asteroid Bennu, which is more than 200 million miles away from Earth.
It was landmark progress in a mission that began with a launch from Cape Canaveral back in 2016.
After nearly two years orbiting Bennu, the spacecraft found a location the size of just a few parking spaces that was thought have the biggest patch of particles small enough to be swallowed up.
It was programmed to shoot out pressurised nitrogen gas to stir up the surface, then suck up any loose pebbles.
Following detailed commands from ground control near Denver, the spacecraft took nearly five hours to make its way down from its orbit around Bennu.
Dodging boulders the size of buildings, it touched down for less than 10 seconds – just long enough to collect samples of cosmic rubble. The asteroid does not have enough gravity for Osiris-Rex to land, so the spacecraft had to try to grab at least 60 grams of the black, crumbly, carbon-rich material with its 13.4-metre robot arm.
The mission’s deputy scientist, Healther Enos from the University of Arizona, described it as “kissing the surface with a short touch-and-go measured in just seconds”. But despite the cheers, it could be a week before scientists know how much, if anything, Osiris-Rex actually managed to grab or whether it will have to be sent back for another try.
NASA says Bennu offers scientists a window into the early solar system as it was first taking shape billions of years ago and flinging ingredients that could have helped seed life on Earth.
Professor Lauretta said the team was overjoyed at Wednesday’s apparently successful mission, which came after more than a decade of planning.
“Even though we have some work ahead of us to determine the outcome of the event – the successful contact, the TAGSAM gas firing, and back-away from Bennu are major accomplishments for the team,” he said.
“I look forward to analysing the data to determine the mass of sample collected.”
Even if Osiris-Rex has grabbed all the asteroid rubble it needs, it won’t arrive back on Earth with its precious samples until 2023.
The mission is a first for the US. Japan is the only country to have previously successfully grabbed asteroid samples.