Scientists in the OSIRIS-REx Sample Curation Laboratory at NASA's Johnson Space Center await the return of an unmanned spacecraft carrying rock and dust samples from the asteroid Bennu that they hope contain "the building blocks of life," says Nicole Lunning, the lead sample curator for the mission. "Going to this type of asteroid is to understand what the precursors were that may have fostered life in our solar system and on Earth," Lunning says. IMAGES AND SOUNDBITES