Rapper and Actor Daniel Curtis Lee performs during the kick off of NASA's Summer of Innovation program at the Jet Propulsion Laboratory in Pasadena, Calif., Thursday, June 10, 2010. Through the program, NASA will engage thousands of middle school students and teachers in stimulating math and science-based education programs with the goal of increasing the number of future scientists, mathematicians, and engineers. Photo Credit: (NASA/Bill Ingalls)

Rapper and Actor Daniel Curtis Lee performs during the kick off of NASA's Summer of Innovation program at the Jet Propulsion Laboratory in Pasadena, Calif., Thursday, June 10, 2010. Through the program, NASA will engage thousands of middle school students and teachers in stimulating math and science-based education programs with the goal of increasing the number of future scientists, mathematicians, and engineers. Photo Credit: (NASA/Bill Ingalls)

Rapper and Actor Daniel Curtis Lee performs during the kick off of NASA's Summer of Innovation program at the Jet Propulsion Laboratory in Pasadena, Calif., Thursday, June 10, 2010. Through the program, NASA will engage thousands of middle school students and teachers in stimulating math and science-based education programs with the goal of increasing the number of future scientists, mathematicians, and engineers. Photo Credit: (NASA/Bill Ingalls)

98-E-03312 (14 April 1998) --- President Bill Clinton (at lectern) addresses employees at NASA's Johnson Space Center (JSC) during an April 14 visit to the Houston facility. Seated behind him (from the left) are JSC Director George W.S. Abbey, U.S. Rep. Nick Lampson (D.-TX), NASA Administrator Daniel Goldin and Houston Mayor Lee Brown. Standing are members of the STS-95 crew: (from the left) Pedro Duque, Chiaki Mukai, U.S. Sen. John H. Glenn Jr. (D.-Ohio), Stephen K. Robinson, Scott E. Parazynski, Steven W. Lindsey and Curtis L. Brown Jr. Brown is commander of the scheduled flight aboard Discovery. Mukai represents Japan's National Space Development Agency (NASDA) and Duque is with the European Space Agency (ESA). Photo Credit: NASA or the National Aeronautics and Space Administration.

S98-05024 (14 April 1998) --- A large crowd of JSC employees listen to President Bill Clinton during an April 14 visit to the Johnson Space Center. On the dais with the President (seated, from the left) are JSC Director George W.S. Abbey, U.S. Rep. Nick Lampson (D.-TX), and Houston Mayor Lee Brown. Standing behind them are members of the STS-95 crew: (from the left) Pedro Duque of ESA, Chiaki Mukai of NASDA, U.S. Sen. John H. Glenn Jr. (D.-Ohio), Stephen K. Robinson, Scott E. Parazynski, Steven W. Lindsey (behind Clinton) and Curtis L. Brown Jr. Out of the frame is NASA Administrator Daniel Goldin who also addressed the crowd. The Chief Executive earlier had gone inside several of the shuttle and ISS crew training facilities and mockups. Photo Credit: Joe McNally, National Geographic, for NASA