Astrobiologists like Jason Dworkin are keenly interested in the origins of life on Earth, but the evidence that they seek was erased long ago by Earth’s geology and chemistry. Fortunately, asteroids like Bennu preserve the solar system’s earliest ingredients - including the carbon-based building blocks of life - which can be retrieved and studied by scientists in a lab on Earth. That’s why NASA is sending a spacecraft called OSIRIS-REx to explore asteroid Bennu and bring back a sample. The material collected by OSIRIS-REx will provide a wealth of data for future generations of scientists, shedding light on one of the solar system's biggest mysteries.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 220.127.116.11.0