Opera singer Denyce Graves sings during the "Salute to Apollo" ceremony at the Kennedy Center for the Performing Arts, Saturday, July 18, 2009 in Washington. The event was part of NASA's week long celebration of the Apollo 40th Anniversary. Photo Credit: (NASA/Bill Ingalls)

Opera singer Denyce Graves sings during the "Salute to Apollo" ceremony at the Kennedy Center for the Performing Arts, Saturday, July 18, 2009 in Washington. The event was part of NASA's week long celebration of the Apollo 40th Anniversary. Photo Credit: (NASA/Bill Ingalls)

Emil de Cou, Conductor of the National Symphony Orchestra, applauds after Opera singer Denyce Graves' perfomance during the "Salute to Apollo" ceremony at the Kennedy Center for the Performing Arts, Saturday, July 18, 2009 in Washington. The event was part of NASA's week long celebration of the Apollo 40th Anniversary. Photo Credit: (NASA/Bill Ingalls)