NASA’s Osiris-Rex Craft Arrives at Asteroid Bennu After 2 Year Space Journey

A NASA spacecraft has arrived at the asteroid known as Bennu after a two year journey. The robot, Osiris-Rex, is NASA’s first sample return mission to an asteroid.

It arrived at a distance of under twelve miles from the ancient rock on Monday. Osiris-Rex will gradually get closer and begin orbiting Bennu on Dec. 31, the Associated Press reports. Using five different instruments to gather data from orbit for a year, the robot is then expected to take samples from the asteroid’s surface using a 10-foot robotic arm.

This mosaic image of asteroid Bennu is composed of 12 PolyCam images collected on Dec. 2 by the OSIRIS-REx spacecraft from a range of 15 miles.NASA/Goddard/University of Arizona
NASA/Goddard/University of Arizona

The capsule of samples should then detach and return to Earth by 2023, hopefully bringing valuable information about Bennu’s makeup. The carbon-rich data could also hold information about the start of our solar system.

With the arrival of Osiris-Rex at Bennu on Monday, and InSight’s landing on Mars last week, it has been an eventful time for NASA of late. Osiris-Rex, an $8 million robot, was built by Lockheed Martin in Littleton, Colorado and launched from Florida’s Cape Canaveral in September 2016.

It’s the first spacecraft to orbit such a small object, but it won’t be the first to make contact: Japan brought back an asteroid sample in 2010. Japan also made history when it landed two rovers on the asteroid Ryugu last September.

The low gravity of smaller objects like asteroids makes it more difficult to target missions. According to Gizmodo, even the heat of the Sun could change the spacecraft’s path. Still, after two years, Osiris-Rex has arrived at Bennu.

Estimated to be roughly 1,600 feet across, Bennu is considered a “potentially hazardous” asteroid. This means that although it’s currently 76 million miles away, it gets fairly close to Earth every six years. Learning more about asteroids can help NASA prepare for the threat of a potential impact.

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