Dr. Christopher Chyba professor of Astrophysical Sciences and International Affairs at Princeton University speaks during the Augustine Commission.

Dr. Christopher Chyba, professor of Astrophysical Sciences and International Affairs at Princeton University, speaks during the Augustine Commission, meeting in Cocoa Beach, Fla. At the request of the Office of Science and Technology Policy, NASA established the Review of U.S. Human Space Flight Plans Committee, known as the Augustine Commission. Chaired by Norman R. Augustine, retired chairman and CEO of Lockheed Martin Corp., the committee is conducting an independent review of ongoing U.S. human spaceflight plans and programs, as well as alternatives, to ensure the nation is pursuing the best trajectory for the future of human space flight - one that is safe, innovative, affordable, and sustainable. Photo credit: NASA/Jim Grossmann