Winter 2020

Bringing Back Bennu

Touch-and-Go Sample Collection a Success for OSIRIS-Rex

The University of Arizona-led OSIRIS-REx mission accomplished a first for NASA when the mission spacecraft collected a sample from a near-Earth asteroid on Oct. 20. It descended to hover just above asteroid Bennu's surface, extended a sample collection arm that briefly touched the surface and collected a sample of the asteroid's rocky material. 

The mission team expedited the stowage process after receiving images showing the spacecraft’s collector head overflowing with material, some of which appeared to be slowly escaping. The team safely stowed the sample for the return journey and confirmed the spacecraft collected well over the targeted minimum of 2 ounces, or 60 grams. 

The composition of the asteroid could shed more light on the origins and evolution of the 4.5-billion-year-old solar system.

Professor Dante Lauretta is the principal investigator of the $1 billion OSIRIS-REx mission. The mission's science operations command center is at the UArizona Lunar and Planetary Laboratory. A total of 150 UArizona undergraduate and graduate students have worked on OSIRIS-REx, and more than 30 alumni have been hired as mission staff. 

OSIRIS-REx builds on UArizona's long legacy of successful planetary exploration. The university has been part of almost every major NASA planetary mission. 

Making History. Again. Mission Facts:

1. Several NASA spacecraft have studied asteroids from a distance, but none has touched an asteroid and returned with material. 

2. The primary sample site, Nightingale, was located in a crater on Bennu’s northern hemisphere and was determined to be the safest spot for the Touch-and-Go sample collection maneuver. 

3. On its return journey, the spacecraft will eject the capsule containing the material from Bennu for landing in the Utah desert on Sept. 24, 2023. 

4. Bennu is about the size of Pusch Ridge in the Santa Catalina Mountains north of Tucson, measuring about 500 meters, or about one-third of a mile. 

5. Bennu is in an unstable orbit, meaning it likely won’t last more than 10 million years before it collides with a planet or falls into the sun. 

6. Evidence of water was discovered locked within the clays that make up the asteroid. Bennu itself is too small to have ever hosted liquid water, but it was likely present at some time on Bennu’s parent body. 

7. Bennu’s temperatures range from 240 degrees Fahrenheit during the day to 100 below zero at night.

8. The mission is officially named the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer. The acronym, Osiris, is the Egyptian god of the underworld, and “rex” means “king” in Latin. 

9. The UArizona-built PolyCam is so named because it is a master of all trades and the best zoom lens created — it can be a microscope, a telescope and anything in between.