WATCH: NASAs OSIRIS-REx mission returns an asteroid soil sample to Earth

July 21, 2024

NASA’s OSIRIS-REx spacecraft dropped off a capsule containing several ounces of rocky, dusty material it collected from the asteroid Bennu on Sunday, successfully closing out the agency’s first attempt to bring an asteroid sample to Earth.

Watch the event in the player above.

About a quarter of the sample will be eventually doled out to researchers across the globe. The majority of it will be archived at NASA’s Johnson Space Center alongside other extraterrestrial materials — including moon rocks and solar wind particles — and reserved for future generations of scientists.

In years to come, “Your grandchildren could write a proposal to NASA to study a piece of the sample with some new technique,” said Mike Moreau, deputy project manager for the OSIRIS-REx mission at NASA’s Goddard Space Flight Center.

Watch NASA’s post-landing news conference in the player above.

But before any scientists get their hands on these pieces of Bennu, the capsule that contains the sample had to touch down in the desert landscape of Utah.

Early on Sunday, researchers involved with the mission gave the go-ahead to follow through with a series of ultra-precise steps that paved the way for the capsule’s safe landing at the Department of Defense’s Utah Test and Training Range.

The OSIRIS-REx spacecraft released the capsule about 100,000 kilometers away from Earth, a distance that’s roughly a third of the way to the moon, Moreau said. That allowed the capsule to cruise through space for four hours, he said, aiming for a mile-wide stretch of the planet’s atmosphere.

WATCH: NASA reviews plan to recover Bennu asteroid sample via OSIRIS-REx

“It’s the equivalent of throwing a dart across the length of a basketball court and hitting the bullseye,” Rich Burns, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center, said during an Aug. 30 news conference.

The capsule’s speed was predicted to reach 27,000 miles per hour as it enters Earth’s atmosphere, with a series of parachute deployments kicking in to slow it down to just 11 miles per hour by the time it landed in the desert, said Sandy Freund, OSIRIS-REx project manager at Lockheed Martin, at the news conference. She noted that that whole process would take just 13 minutes.

Researchers then transferred the capsule with a sling that hangs under a helicopter to a temporary clean room for evaluation to prepare it for shipping to its ultimate home — Johnson Space Center in Houston.

Keeping the sample free of any earthly contaminants is a top priority. Scientists at the landing site were tasked with scooping up air and soil samples from the local environment so that if something unexpected is detected in the Bennu sample, they can determine its origin, Moreau said. Evidence so far suggests the OSIRIS-REx team carried out their mission without a hitch.

“Today marks an extraordinary milestone not just for the OSIRIS-REx team but for science as a whole,” Dante Lauretta, principal investigator for OSIRIS-REx at the University of Arizona, Tucson, said in a statement released by NASA. “Successfully delivering samples from Bennu to Earth is a triumph of collaborative ingenuity and a testament to what we can accomplish when we unite with a common purpose.

How did OSIRIS-REx collect a sample from Bennu?

Bennu is billions of years old. The asteroid dates back to the dawn of the solar system, when its planets — including Earth — were in their very infancy.

Bennu is roughly the size of the Empire State Building, Lauretta said in the Aug. 30 news conference.

“It literally is a droplet made out of rock, gravel and boulder that are barely held together by their own microgravity,” Lauretta said. He added that he refers to Bennu as the “trickster” asteroid because of the many surprises it presented to the OSIRIS-REx team during their mission.

When the spacecraft first arrived at Bennu in 2018, about two years after its initial launch, researchers realized that the asteroid’s surface was covered in boulders, Moreau said. That made identifying a safe sample collection spot a challenge.

Once the team did find an ideal location — dubbed Nightingale — they expected OSIRIS-REx to pluck its sample from a solid expanse of rock, Lauretta said. But when the spacecraft made its collection attempt in 2020, Moreau said they were shocked to find the surface crumbled immediately.

“It was like jumping into a ball pit. The material is so loosely held together,” Moreau said. “And when the nitrogen gas fired [from OSIRIS-REx] to collect the sample, the whole surface disintegrated under the spacecraft.”

After OSIRIS-REx released the capsule containing that sample in Earth’s direction, it entered a new leg of its journey. Though the spacecraft wasn’t initially expected to pursue a follow-up mission, researchers have planned a six-year journey that will allow it to tail another asteroid, named Apophis, when it makes a close pass by our planet in 2029.

Moreau said that Earth’s gravitational pull may influence Apophis’s physical structure as it swings by Earth, including by potentially causing landslides on the asteroid’s surface. The spacecraft — which at that point will be renamed OSIRIS-APEX — will be closely monitoring exactly what happens on the asteroid, plus analyzing its composition and properties.

What could the Bennu sample tell us?

Researchers believe Bennu can serve as an ancient clue to help us understand the evolution of the solar system.

The rocks and dust collected by OSIRIS-REx should shed light on what types of minerals and materials were present at the formation of asteroids like Bennu, in addition to planets including Earth, said Michelle Thompson, a planetary scientist at Purdue University. The goal, she added, is to “create an inventory for the building blocks of the solar system.”

Bennu is a carbonaceous asteroid, a category of asteroids that harbor organic molecules dating back to the early solar system. Remote analysis found hydrated minerals that contain structural water on Bennu, Thompson said, which means liquid water likely once existed on its parent body before the asteroid broke off.

That doesn’t mean there is any life on the asteroid, she emphasized. But one core theory of how life got its start on Earth posits that asteroids like Bennu helped deliver the basic ingredients when they smashed into our young planet.

If life on Earth is like a brick house, Thompson explained, Bennu can tell us about the individual bricks that helped build it.

“By targeting an asteroid that hasn’t really been altered in a significant way over the history of the solar system, we can kind of take a time machine back and see what those organic molecules look like,” she said.

Thompson will be among the first few researchers to study the samples delivered by OSIRIS-REx. She specializes in planetary bodies that don’t have an atmosphere, like asteroids or the moon. Because Bennu has no shield to protect it as it travels through space, the asteroid is routinely struck by forces like solar wind and dust particles, Thompson noted.

She said she’ll focus on parts of the sample that represent the first few millimeters of Bennu’s surface, which are most affected by the asteroid’s exposure to interplanetary space. By comparing Bennu’s “skin” to more protected materials farther below, Thompson explained, she’ll be able to evaluate which characteristics of Bennu have been around since its initial formation, and which have been altered over the past several billion years.

Thompson has also worked with lunar samples brought to Earth during the Apollo missions of the 1960s and 1970s. She noted that researchers continue to learn about the moon’s evolution thanks to those materials, and that the same will be true of these pieces of Bennu.

“As techniques have evolved, and as they’ll continue to get better in the future of the OSIRIS-REx samples, they’re really going to be like the gift that keeps on giving,” she said.

ncG1vNJzZmivp6x7sa7SZ6arn1%2Bjsri%2Fx6isq2ejmLamusKeZrCZpJi1brjIr5xmmZ6Ytqa602aYrKyVp7yqsIysmKaonJp6ra3Nnapmp55isqK%2B06FkoqZdoa60wIylnKBln5t6r63SmmSoq5mntrR50Z6vZqWZqMCqu80%3D