Gregory H. Johnson (Col., USAF, Ret.) is the President and Executive Director for the Center for the Advancement of Science in Space (CASIS). He is responsible for leading staff in the identification of novel applications and the development of new partnership opportunities which will advance utilization of our nation's orbiting laboratory. Prior to his current position, he was a decorated officer and pilot with the U.S. Air Force. Johnson flew 34 combat missions in support of Operation Desert Storm and 27 missions during Operation Southern Watch. During his nearly 25 years in the U.S. Air Force, he logged over 5,000 flight hours in more than 50 different aircraft. In 1998, Johnson was selected as a NASA Astronaut and ultimately piloted two Space Shuttle missions (STS-123 and STS-134, both aboard Space Shuttle Endeavour), where he spent nearly 32 days in orbit and contributed to the assembly of the International Space Station. He later served on rotational assignment as the associate director of external programs at NASA Glenn Research Center in Cleveland, Ohio, during which he managed all public affairs, outreach and educational programs at the Center. Johnson holds a Bachelor's of Science in aeronautical engineering from the U.S. Air Force Academy, a Master's of Science in flight structures engineering from Columbia University, and a Master's of Business Administration from University of Texas at Austin.