After orbiting the near-Earth asteroid Bennu for nearly two years, NASA's OSIRIS-REx spacecraft on Tuesday successfully touched down and reached out its robotic arm to collect a sample from the asteroid's surface, CNN reports.
The sample will be returned to Earth in 2023.
To achieve this historic first for NASA, a van-size spacecraft had to briefly touch down its arm in a landing site called Nightingale. The site is the width of a few parking spaces.
The arm reached out to collect a sample, which could be between 2 ounces and 2 kilograms. Then, the spacecraft backed away to safety.
On Tuesday night, the OSIRIS-REx team will go through the data being sent back by the spacecraft.
The agency will be able to confirm if a sample was successfully collected later and images of the event will be available Wednesday on NASA's site.
"It's a historic first mission for NASA, returning an asteroid sample, and it's hard," said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate, during a Monday press conference.
The site itself is nestled within a crater the size of a tennis court and ringed in building-size boulders.
Located more than 200 million miles from Earth, Bennu is a boulder-studded asteroid shaped like a spinning top and as tall as the Empire State Building. It's a "rubble pile" asteroid, which is a grouping of rocks held together by gravity rather than a single object.
The mission -- which stands for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer -- launched in September 2016.
Since arriving at Bennu, the spacecraft and its cameras have been collecting and sending back data and images to help the team learn more about the asteroid's composition and map the best potential landing sites to collect samples.
Bennu has an orbit that brings it close to Earth, which is why it's considered to be a near-Earth asteroid. One of its future approaches could bring it perilously close to Earth sometime in the next century; it has a one in 2,700 chance of impacting our planet, according to CNN.
The samples from Bennu could help scientists understand not only more about asteroids that could impact Earth but also about how planets formed and life began.
The team estimates that they will have a mass measurement of the sample on Saturday. By October 30, NASA will confirm if the spacecraft collected enough of a sample or if it needs to make another sample collection attempt in January at another landing site called Osprey.
If everything runs smoothly, the spacecraft and its prized sample will begin the long journey back to Earth next year and land the sample on Earth in 2023.