Published: Tue, December 04, 2018
Science | By

After two-year journey, NASA Osiris-Rex spacecraft arrives at asteroid Bennu

After two-year journey, NASA Osiris-Rex spacecraft arrives at asteroid Bennu

If it collided with Earth, Bennu would probably cause a crater.

It is the first US attempt to gather asteroid samples for return to Earth, something only Japan has accomplished so far.

Osiris-Rex is the first United States mission created to return a piece of an asteroid to Earth.

The sampler head is stored in the Sample-Return Capsule (SRC) and OSIRIS-REx will return to Earth.

But its orbit drifts 0.18 miles each year toward the sun, and OSIRIS-REx will enable researchers to understand why and to predict Bennu's movements. The rapid rotation also sends small rocks on the asteroid's surface flying into space, meaning there's nothing there for the spacecraft to collect. Bennu's nearly 500 meters in diameter, and rotates only once every 4.3 hours.

In August, the craft snapped its first image of asteroid Bennu.

After a two-year chase, a Nasa probe has reached the ancient asteroid Bennu.

Meanwhile, a Japanese probe is circling an asteroid named Ryugu, about double the size of Bennu, with a plan to bring home some specks of space dust. So close that it's considered a Potentially Hazardous Object (PHO), an object with an orbit that brings it close to Earth, and that's large enough to do serious damage if it struck.

NASA's OSIRIS-REx spacecraft captured this photo of the asteroid Bennu on November 16, 2018, from a distance of 85 miles.


Asteroids may have played a role in the origins of life here on Earth by delivering organic molecules to our planet in its early days.

Scientists hope it will reveal more about the early formation of the solar system, as well as how to find precious resources like metals and water in asteroids. OSIRIS-REx fired its thrusters for a small burn, putting it about 4.3 miles from Bennu, marking the end of its journey to the asteroid.

"The TAGSAM exercise is an important milestone, as the prime objective of the OSIRIS-REx mission is to return a sample of Bennu to Earth", said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson.

Then, in 2020, it will reach out with its robotic arm and touch the asteroid in a maneuver Rich Kuhns, OSIRIS-REx program manager with Lockheed Martin Space Systems in Denver, described as a "gentle high-five". Getting their hands on pristine asteroid material might also yield clues about how to mine them for valuable materials and defend against wayward ones that might threaten Earth.

Below is a series of images taken by OSIRIS-REx at a distance of about 80 km (50 mi.) The images constitute one full revolution of the asteroid.

Contact with Bennu will not significantly change its orbit or make it more risky to us, Lauretta stressed.

The 4,560-pound spacecraft was launched atop an Atlas V rocket from Cape Canaveral, Florida, on September 8, 2016. Its odometer read 1.2 billion miles (2 billion kilometers) as of Monday. OSIRIS-REx was finally at the doorstep of its new home.

Now that OSIRIS-REx - short for Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer - has arrived at Bennu, the eight-foot-long spacecraft will spend more than a year and a half surveying the asteroid, in preparation to carefully descend to the ground and perform its ambitious, primary mission.

Like this: