"This is going to be the largest sample of an extraterrestrial object returned to Earth since end of the Apollo missions over 40 years ago," said Edward Beshore, deputy principal investigator for the mission, who is based at the University of Arizona, Tucson.
The probe will arrive at the asteroid in 2018, study it, then bring back the sample in 2023.
1999 RQ36 is made of materials "almost identical to those that were present when the solar system was formed about 4.5 billion years ago," he said. That means studying this asteroid could yield greater understanding about the sources of organic molecules and water that gave rise to life.
This asteroid, like the one that will fly by on Feb. 15, is considered a near-Earth object. The mission would further clarify the threat that this particular object poses, and better predict the orbits of other near-Earth asteroids, Beshore said.
Scientists at the University of Arizona are collaborating with NASA and Lockheed Martin Space Systems on this mission.
To better predict the orbits of hazardous objects, this group is looking at the Yarkovsky effect, a force created when the asteroid absorbs sunlight and re-radiates it as heat.
The effect is, at first glance, quite small -- Beshore cited his colleague Steven Chesley's comparison of this effect to the force you feel when you hold grapes in your hand. But over time, it's an important consideration when trying to understand where an asteroid is headed.
"That force, applied over millions of years, can literally move mountains of rock around," Beshore said.
We can't say this enough: Don't panic over it.