NASA’s OSIRIS-REx Mission Arrives At Asteroid Bennu — What’s Next For The Intrepid Spacecraft?

NASA/Goddard/University of Arizona

NASA’s first asteroid-sampling mission, the OSIRIS-REx, has finally arrived at its destination — a diamond-shaped space rock that floats some 76 million miles from Earth and goes by the name of Bennu.

To get there, OSIRIS-REx has chased Bennu for a little more than two years, traveling 1.24 billion miles through space to catch up with the 1,650-foot-wide asteroid, NASA announced earlier today.

Today’s triumph comes exactly one week after the space agency successfully landed a spacecraft on Mars — the first one to touch down on Martian ground in six years and the eighth to ever make it to the red planet.

“Achievement unlocked: ‘We have arrived!'” NASA wrote on Twitter a few hours ago.

The much-awaited rendezvous with the near-Earth asteroid occurred at around 12 p.m. ET, after the OSIRIS-REx spacecraft fired its thrusters for a small burn and pulled within 12 miles of Bennu’s surface. According to, due to the vast distance between Earth and the OSIRIS-REx, it took seven minutes for flight controllers at Lockheed Martin — which built the spacecraft — to receive confirmation that the intrepid probe arrived at Bennu.

What’s Next For The OSIRIS-REx Mission

Short for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer, the OSIRIS-REx spacecraft was sent to collect regolith samples from asteroid Bennu. The spacecraft is slated to bring back least 60 grams (equal to about 30 sugar packets) of dust and gravel from the space rock’s boulder-strewn surface.

Now that it has finally reached its target, the OSIRIS-REx is currently flying along the space rock, waiting to enter its orbit. During the next few weeks, the probe will perform five flybys of the asteroid’s poles and equator before it finally slides into Bennu’s orbit on December 31.

As the Inquisitr previously reported, these upcoming flybys will bring OSIRIS-REx as close as 4.3 miles of the asteroid’s rugged terrain, so that the probe can map the space rock and gather fresh data on Bennu’s mass and rotation.

“The spacecraft will spend almost a year surveying the asteroid with five scientific instruments with the goal of selecting a location that is safe and scientifically interesting to collect the sample,” NASA officials explained in a statement.

The approach to Bennu has enabled OSIRIS-REx to take a new series of photos of the near-Earth asteroid. The images — 36 in total — were taken from a distance of around 50 miles over a period of four hours and 18 minutes.

The new frames capture the asteroid’s full rotation and were put together in a GIF, released on Twitter after the probe’s arrival at Bennu.

Today’s milestone kicks the mission into full gear, marking the beginning of science operations. However, OSIRIS-REx won’t swoop down to Bennu’s surface until July 2020, when the spacecraft will make a brief contact with the asteroid to snag the regolith samples.

The probe won’t actually land on the asteroid, but rather descend to its surface to blast it with nitrogen gas and vacuum dislodged fragments for collection.

An artist’s illustration showing the OSIRIS-REx spacecraft collecting a sample from Bennu.
An artist’s illustration of the OSIRIS-REx spacecraft collecting a sample from Bennu.Featured image credit: NASA

If everything goes as planned, OSIRIS-REx will head back home in March 2021 and deliver the precious samples in September 2023.

Why Asteroid Bennu?

Bennu is a carbon-rich asteroid estimated to be around 45-billion-years-old. The space rock dates back to the beginning of our solar system and likely took shape some 10 million years after our planets were formed.

“Bennu is a time capsule from the early solar system, having been preserved in the vacuum of space,” states NASA.

Because the asteroid is so old, scientists believe that Bennu could contain organic molecules similar to those which ignited the spark of life on Earth. Studying this ancient relic could help us unravel our cosmic past and reveal more clues on the origin of life.

When NASA chose to send its first-asteroid sampling mission to Bennu, the space agency was looking at the space rock’s size, age, composition, and proximity to our planet.

The asteroid measures just 492 meters across — “which is a bit larger than the height of the Empire State Building in New York City,” notes NASA — and has a rotational period of 4.3 hours. This means that Bennu is big enough to move relatively slowly and retain regolith as it spins around its axis.

Although the asteroid is currently drifting through space between the orbits or Earth and Mars, Bennu actually originated further out in the solar system. The space rock was likely forged in the Asteroid Belt that stretches between Mars and Jupiter and is believed to have broken off from a larger asteroid around 700 million to 2 billion years ago. This massive collision pushed Bennu closer to our neck of the woods, which explains the asteroid’s current location.

Come December 31, Bennu will become the smallest celestial body to ever be orbited by a manmade spacecraft.