A spacecraft with a University of Calgary connection is on its way to rendezvous with near-earth asteroid Bennu. Launched on Sept. 8 of this year, OSIRIS-REx will approach the rocky body in October 2018 and conduct a one-year survey of its surface. This is all a leadup to the ultimate close encounter — the collection and return of a sample from the asteroid’s surface.
Department of Geoscience associate professor Alan Hildebrand is part of the science team that guided development of the OSIRIS-REx Laser Altimeter (OLA), an advanced light detection and ranging system that will map the surface of Bennu. The Canadian Space Agency is funding OLA as Canada’s contribution to the NASA mission.
“The main purpose of the OLA system is to provide high-resolution topographical information about Bennu during the mission,” says Hildebrand. “OLA will survey the asteroid’s contours and features, creating an extremely accurate 3D model. This will help us identify and select where to collect the sample.”
Why we study asteroids
Asteroids formed from the primal leftovers of the planets. Missions like OSIRIS-REx help scientists investigate the formation of our solar system and the origin of water and organic material on Earth. OSIRIS-REx is short for the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer.
And then there’s the issue of impact hazards. “Bennu has a small chance of impacting the Earth in 150 to 200 years,” says Hildebrand. “Whether or not it does depends on the Yarkovsky Effect, a small force acting on the asteroid. One purpose of the mission is to explore this effect so we’ll know for sure if this asteroid might impact our planet in the future."
Additional contribution to the mission
Lincoln Hanton is a research assistant working with Hildebrand. He has measured physical properties such as elasticity and strength of the simulant developed to mimic the surface of Bennu.
“We have designed and produced material that simulates what TAGSAM — the spacecraft’s sample collector — might encounter on the asteroid,” says Hanton. “This simulant was used by Lockheed-Martin during the sampler’s development and testing.”
“From what I’ve learned working on this project, Bennu will have a different composition than the few other asteroids studied by spacecraft to date,” Hanton adds. “Bennu is a primitive carbonaceous asteroid that hasn’t changed much since the formation of the solar system.”
Seven-year mission ends in 2023
OSIRIS-REx could return up to two kilograms of material from Bennu’s surface. The sample analysis, which will take months, if not years, will reveal the properties of the asteroid, how it formed and how it moves. The Canadian Space Agency will own four per cent of the precious sample and the tentative plan is for it to be curated at the University of Calgary in ultraclean conditions where researchers can study it.
Hanton was at Cape Canaveral, Florida to watch the launch of OSIRIS-REx. Will he witness its return?
“It was really amazing, watching the rocket launch, knowing that in a small way, you contributed to the mission,” Hanton says. “And while I’m not sure where I’ll be in seven years, it would be incredible to see the mission come full circle by witnessing the return of the sample capsule over the Utah desert in September 2023. I’ll have to wait and see.”
To learn more about OSIRIS-REx, you can watch these NASA Goddard videos:
Follow the mission on Twitter @OSIRISREx