OSIRIS-REx mission: To Bennu and Back

Posted at 8:42 PM, Apr 29, 2016

The OSIRIS-REx spacecraft being built at Lockheed Martin is going to an asteroid that could explain how life began on our planet- and could also crash into it.

Samples from the asteroid Bennu will provide new insight into the history of our solar system.

The carbon-rich asteroid could also provide clues about the beginning of life on Earth.

"Primitive asteroids have not significantly changed since they formed nearly 4.5 billion years ago," Lockheed Martin experts said. "Because of this, we hope to find organic molecules on Bennu like those that may have led to the origin of life on Earth."

"On planets like Earth, the original materials have been altered by geologic activity," researchers said. "Bennu is like a time capsule where all the chemistry, including possible organic particles, is relatively unaltered."

(The 3D-printed models of the Bennu asteroid and the OSIRIS-REx are not to scale.)

The OSIRIS-REx is about 3 meters across. The asteroid is about 500 meters in diameter.

Bennu orbits the Sun and comes very close to Earth every six years.

In fact, Bennu has a "high probability" of impacting Earth in the late 22nd century, researchers said. 

Knowing its composition could help plan future missions to deflect it.

If Bennu hit Earth it would be a 3,000-megaton explosion - like hundreds of nuclear weapons going off in one place at the same time, project engineers said. 

Researchers at Lockheed Martin created a simulated asteroid wall, 45-feet high and 45-feet wide, so they can practice using the tools and sensors they'll need to make contact with surface of Bennu and collect a sample.

(PHOTO: A project engineer, standing in front of the "asteroid wall," holds the touch-and-go sample collector.)

A project engineer explained how the touch-and-go sample collector (TAGSAM) works. It will make contact with the asteroid Bennu for three to five seconds and use pressurized gas to kick up rocks and dust. The gas will escape through filters but the samples from the surface will be trapped inside.

The engineers wouldn't let us see or photograph the underside of the TAGSAM. (Apparently, the bottom is top secret.)

A robot arm will transfer TAGSAM into the capsule that will carry it back to Earth.

OSIRIS-REx is set to launch from Cape Canaveral, Florida on Sept. 8, 2016.

It will be launched into space on United Launch Alliance's Atlas V 411.

After a few hours, it will detach from the rocket and continue the rest of the way to Bennu under its own power. 

OSIRIS-REx is expected to arrive at Bennu in 2018.

It will fly around the asteroid for about a year, taking photos of the surface and studying its composition. Previous studies of Bennu show it is not solid rock but a loose collection of boulders, rock and dust.

The sample capsule should return to Earth and land in a remote part of Utah in late 2023.