A decade after launch, NASA’s OSIRIS-REx mission has transformed our understanding of asteroid Bennu, returned a piece of the early solar system to Earth, and opened a new chapter of exploration.
OSIRIS-REx began with a fundamental question: What can an asteroid tell us about where we came from?
A decade later, the answer is revealing a remarkably complex story.
For Lockheed Martin, OSIRIS-REx represents another milestone as we continue exploring the solar system.
The spacecraft was built to reach the unknown.
Ten years later, the mission is coming to an official close, but the findings it has uncovered are only just beginning. And with the follow-on mission, OSIRIS-APEX, the spacecraft will continue to explore and make new scientific discoveries about the asteroid Apophis in 2029.
Let’s rewind to the beginning.
On Sept. 8, 2016, NASA’s OSIRIS-REx spacecraft launched on a journey unlike any U.S. mission before it.
Its destination was Bennu, a small, carbon-rich asteroid that formed billions of years ago. Its mission: travel to Bennu, study its surface, collect a sample, and deliver it to Earth for scientists to examine. OSIRIS-REx accomplished all of it.
Designed, built, and operated by Lockheed Martin, the spacecraft became the first U.S. mission to collect and return a sample from an asteroid. On Sept. 24, 2023, its sample return capsule landed in the Utah desert carrying 121.6 grams of material from Bennu, more than twice the mission’s minimum requirement.
The achievement capped seven years of exploration. But the discoveries were just beginning.
Built for the unknown
OSIRIS-REx drew on decades of our experience building spacecraft for planetary exploration, incorporating technologies and design approaches from missions including Mars Reconnaissance Orbiter, MAVEN, and Stardust. Lockheed Martin also operated the spacecraft from its Mission Operations Centre.
And this expertise was needed, as Bennu presented plenty of challenges.
When OSIRIS-REx arrived in December 2018, the asteroid looked dramatically different from what scientists expected. Instead of a smooth surface, Bennu was covered in boulders, rocks, and treacherous terrain.
Lockheed Martin engineers and mission operators worked with NASA and other mission partners to operate the spacecraft around Bennu and identify a suitable sampling location. The spacecraft’s Natural Feature Tracking system allowed it to autonomously compare images of the asteroid’s surface with onboard maps as it descended.
The solution was a small crater called Hokioi.
On Oct. 20, 2020, OSIRIS-REx made history. The spacecraft briefly touched Bennu’s surface with its robotic arm, firing nitrogen gas into the regolith. The burst stirred up rocks and dust, capturing them inside the Touch-And-Go Sample Acquisition Mechanism, or TAGSAM.
The manoeuvre worked remarkably well. So well, in fact, that material began escaping from the collection head immediately after the spacecraft backed away. OSIRIS-REx had exceeded mission expectations.
Today, scientists are unlocking a history book covering the early formation of the solar system, over 4.5 billion years ago.
We now know Bennu contains abundant carbon, nitrogen, and organic compounds, along with molecules important to biology. Scientists have identified most of the protein amino acids found in life, all five nucleobases used by DNA and RNA, and sugars including ribose and glucose. The samples also contain phosphate minerals, providing evidence that Bennu’s parent body once experienced significant interaction with liquid water.
Together, these discoveries are helping scientists better understand how the chemical ingredients associated with life were formed and distributed throughout the solar system.
But Bennu also challenged scientists’ understanding of how asteroids behave.
During sample collection, TAGSAM sank much farther into Bennu’s surface than expected, revealing that the asteroid’s exterior is remarkably weak and porous. Rather than being a solid rock, Bennu is a loosely bound collection of material. The spacecraft’s observations and the returned samples are giving researchers an unprecedented look at how these small worlds formed, evolved, and changed over billions of years.
An end date does not mean an end of discovery.
But the spacecraft itself never came home.
After releasing the capsule, it is now continuing into deep space under a new name: OSIRIS-APEX. Its next destination is another asteroid, Apophis, which it will study following the asteroid’s close approach to Earth in 2029. OSIRIS-APEX aims to provide first-of-its-kind high-resolution observation of a stony asteroid class, differing from the carbonaceous composition of Bennu.
While Sept. 30 closes the formal chapter of this extraordinary mission, the journey isn’t over. The samples themselves will still be available for future scientists to request and study. And the observations OSIRIS-APEX will take of Apophis will help unlock the next chapter of exploration.
