Upon a successful return to Earth next year, the OSIRIS-REx spacecraft will be the first American mission to retrieve a sample from an asteroid. But NASA announced last week that the story won’t end there. NASA has extended the University of Arizona-led mission, and after drop-off, the spacecraft will continue on to study near-Earth asteroid Apophis for 18 months.
In this second mission, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) will be renamed to OSIRIS-APEX (OSIRIS-Apophis Explorer.) The extension adds another $200 million to the mission cost cap.
OSIRIS-REx, led by UA professor Dante Lauretta, launched from Earth in 2016 and headed toward the asteroid Bennu. In 2020, the spacecraft briefly touched down on the asteroid’s surface, collecting an estimated pound of extraterrestrial dust and rocks. OSIRIS-REx is expected to return to Earth orbit in September 2023 and deliver the capsule of samples, which researchers will study for information about our early solar system and potentially the origins of life.
Now, the spacecraft is planned to head back into space on the Apophis mission only a month after returning the samples.
“Apophis is one of the most infamous asteroids,” said OSIRIS-REx deputy principal investigator Dani DellaGiustina, who is also a UA assistant professor. “When it was first discovered in 2004, there was concern that it would impact the Earth in 2029 during its close approach. That risk was retired after subsequent observations, but it will be the closest an asteroid of this size has gotten in the 50 or so years… It gets within one-tenth the distance between the Earth and moon during the 2029 encounter. People in Europe and Africa will be able to see it with the naked eye, that’s how close it will get. We were stoked to find out the mission was extended.”
The university stated that OSIRIS-APEX will not collect a sample on this next mission, but when it reaches Apophis, it will study the asteroid for 18 months and collect data along the way. It also will make a maneuver similar to the one it made during sample collection at Bennu, by approaching the surface and firing its thrusters. This event will expose the asteroid’s subsurface, to allow mission scientists to learn more about the asteroid’s material properties.
“OSIRIS-APEX is a manifestation of a core objective of our mission to enable the next generation of leadership in space exploration,” Lauretta said.