Asteroid Sample Set to Arrive on Earth in Fall 2023

The OSIRIS-REx spacecraft is carrying a sample from the asteroid Bennu.

By Stephanie Mlot

NASA’s first asteroid sample return spacecraft, OSIRIS-REx, is on track to deliver a sample of asteroid Bennu to Earth by September 2023.

The maneuver isn’t as simple, though, as dropping a package onto the planet’s doorstep. OSIRIS-REx (Origins Spectral Interpretation Resource Identification Security-Regolith Explorer) must approach at a precise speed and direction to properly deliver its sample return capsule.

Angled too high, and it will skip off Earth’s atmosphere; angled too low, and it will burn up before arrival, according to Mike Moreau, deputy project manager at NASA’s Goddard Space Flight Center. To ensure safe delivery, the OSIRIS-REx team will “gradually adjust” the spacecraft’s trajectory, inching it closer to Earth.

The unmanned probe last month made its first course correction, gently moving into a flight path that will take it about 1,367 miles from Earth. Eventually, engineers will maneuver OSIRIS-REx even closer: 155 miles off the surface—close enough for the sample capsule’s precision landing via parachute at the US Air Force’s Utah Test and Training Range in the Great Salt Lake Desert.

“Over the next year, we will gradually adjust the OSIRIS-REx trajectory to target the spacecraft closer to Earth,” said Daniel Wibben, trajectory-and-maneuver design lead with KinetX Inc., which works closely with the Lockheed Martin team flying the ship. “We have to cross Earth’s orbit at the time that Earth will be at that same location.”

After a September 2016 launch, OSIRIS-REx took more than two years to reach Bennu, where it spent another two-plus years surveying the asteroid before collecting a sample in 2020.

“Asteroids can act as time capsules,” NASA says, “preserving the earliest history of our solar system and possibly even chemical signatures of the ancestral building blocks of life—something scientists could learn more about by studying the Bennu samples in the lab.”

The space agency is working closely with the Air Force and Army to practice capsule retrieval and transport. NASA’s Johnson Space Center in Houston built a new curation lab specifically to store the sample; engineers and curation experts, meanwhile, are designing specialized gloveboxes, tools, and storage containers to preserve the sample in pristine condition.

After returning the Bennu sample to Earth, OSIRIS-REx will continue on an extended mission—under the name OSIRIS-APEX—to asteroid Apophis.

Originally published at https://www.pcmag.com.