A piece of history: What to know about the University of Arizona OSIRIS-REx mission

Researchers at the University of Arizona's Lunar and Planetary Laboratory waited seven years for the return of its NASA spacecraft OSIRIS-REx.

The spacecraft launched in 2018 with the goal of reaching Bennu, a near-Earth asteroid made of carbon-rich materials that helped form the planets 4.5 billion years ago. OSIRIS-REx is the first U.S. mission to collect an asteroid sample and bring it back to Earth.

On Sunday morning, the asteroid material successfully reached Earth's surface, landing in the Utah desert as planned. It was the first time extraterrestrial material from beyond the moon's orbit was brought to Earth, according to the University of Arizona.

Here's everything you should know about the sample's arrival and the plans for the OSIRIS-REx spacecraft.

Why is it called OSIRIS-REx?

OSIRIS-REx is an acronym for words that relate to the mission's "major concepts and goals," according to the University of Arizona.

The second "s," for instance, stems from "security," which is relevant to the project because one of the mission goals is to "measure and learn about the forces that can change an asteroid's orbit," according to the university, and the asteroid Bennu, has an "unstable orbit," so there's a chance it could collide with Earth in the 22nd century.

The REx part is derived from "regolith explorer." Regolith is the loose material that's on top of bedrock. Another goal of the mission is to "document the texture, geochemistry and other properties of the surface material at the sampling site," according to the university. Rex also means "king" in Latin.

The spacecraft was named in honor of the ancient Egyptian god Osiris. Inspired by his interest in mythology, principal investigator Dante Lauretta thought of the name while "doodling on a pad trying to capture the themes of the mission," according to the University of Arizona's OSIRIS-REx mission website.

What discoveries could the OSIRIS-REx sample bring?

The University of Arizona's Lunar and Planetary Laboratory expects the asteroid sample to foster decades of research.

"The material it returns will be the largest sample brought back from space since the Apollo moon landings in the 1960s and 70s and will help ensure that the University of Arizona remains at the forefront of planetary exploration," according to a university statement about the mission.

By studying Bennu, scientists hope to get a glimpse of Earth's past. In addition to being "one of the more potentially hazardous asteroids," Bennu has organic molecules that "gave rise to the origin of life and Earth's oceans," according to the university.

The University of Arizona team hopes the sample could help researchers answer a variety of questions, including whether we're alone in the universe, how Earth's oceans formed, ways to stop asteroids from hitting Earth and whether asteroids can be used as fuel.

Why was University of Arizona chosen to lead this mission?

The University of Arizona has a history of being at the forefront of space research.

For instance, the Lunar and Planetary Laboratory led surface operations for the Phoenix Mars Lander mission that launched in 2007 and landed on Mars in 2008.

University of Arizona faculty have also contributed to the Parker Solar Probe, the Juno mission to Jupiter, the MARS Renaissance Orbiter, the Near-Earth Object Surveyor, the Mars MAVEN Orbiter, the Lunar Reconnaissance Orbiter and the Mars Odyssey Orbiter.

The OSIRIS-REx mission was proposed in 2004 by Lauretta, who oversees the mission team, and the laboratory's former director, Michael Drake. They spent seven years trying to convince NASA to fly the spacecraft, according to the University of Arizona.

Eventually, OSIRIS-REx was launched on Sept. 8, 2016.

What has happened since the launch?

After traveling more than a billion miles through space, OSIRIS-REx arrived at Bennu in December 2018. OSIRIS-REx orbited Bennu from 2018 to 2020 as researchers studied the asteroid.

During the observation period, the mission team discovered that Bennu's makeup contains a high concentration of water-rich materials. This means Bennu may "contain the molecular precursors like other asteroids that came into contact with our planet in the past and that gave rise to the origin of life and Earth's oceans," according to the university.

"That is a really exciting finding because asteroids like Bennu may have delivered water to the surface of Earth early in its history, at the very start of or near the beginning of the solar system," said Anjani Polit, a mission implementation systems engineer for OSIRIS-REx.

The OSIRIS-REx team was also surprised by how "rough and rocky" the asteroid's surface was, which created challenges in obtaining a sample, Polit said.

"We had expected there to be sandy patches on the asteroid that we could easily sample," Polit said. "But instead, we had to completely rethink how we were doing sample site selection and find a way to get into a much smaller spot anticipated to collect the sample."

By October 2020, the OSIRIS-REx had collected pieces of Bennu and started its three-year journey back to Earth.

OSIRIS-REx glided by Earth on Sunday to drop off a sample capsule filled with pieces of the Bennu asteroid. As the capsule made its brief descent through Earth's atmosphere, OSIRIS-REx flew onto its next mission as OSIRIS-APEX — short for OSIRIS-APophis EXplorer.

What will scientists do with the sample?

Pieces of Bennu will be stored in a new lab that was made specifically for the sample at NASA's Johnson Space Center in Houston.

Lauretta's team will keep a quarter of the sample to study, while the rest will be curated and preserved for future use by the world's science community.

The samples and their initial analysis will be revealed during a press conference on Friday, Oct. 6.

"The OSIRIS-REx mission has already surprised us in so many ways," said University of Arizona President Robert C. Robbins. "I know that it will continue to do so as our scientists dig into the sample and work to reveal more about the origins of the solar system and potentially life itself."

What's next for the OSIRIS-REx spacecraft?

The OSIRIS-REx spacecraft isn't done with its work. It has another nearby asteroid to explore.

While the OSIRIS-REx team examines the Bennu sample, a new team at the University of Arizona will lead OSIRIS-APEX, the second chapter of the mission.

OSIRIS-APEX will travel six years toward Apophis, a stony asteroid that will orbit close to Earth in April 2029. Researchers plan to map the Apophis asteroid and study the impact of Earth's gravitational force for 18 months.

This mission has the potential "to enrich our understanding of the solar system and potentially hazardous asteroids even further," according to the university.

This article originally appeared on Arizona Republic: University of Arizona OSIRIS-REx sample landed on Earth. What to know