Retired Navy Captain and commander of Apollo 17 Eugene Cernan, center, is flanked by Apollo 11 Commander Neil Armstrong, left, and A. Thomas Young, as he testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

Retired Navy Captain and commander of Apollo 17 Eugene Cernan testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden makes a point as he testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

Apollo 11 Commander Neil Armstrong, left, testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington as retired Navy Captain and commander of Apollo 17 Eugene Cernan looks on. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden makes a point as he testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

Apollo 11 Commander Neil Armstrong, left, and retired Navy Captain and commander of Apollo 17 Eugene Cernana, confer prior to testifying at a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

Retired Navy Captain and commander of Apollo 17 Eugene Cernan, center, testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington as Apollo 11 Commander Neil Armstrong, left, looks on. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

Apollo 11 Commander Neil Armstrong makes a point as he testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)

NASA Administrator Charles Bolden makes a point as he testifies during a hearing before the House Science and Technology Committee, Tuesday, May 26, 2010, at the Rayburn House office building on Capitol Hill in Washington. The hearing was to review proposed human spaceflight plan by NASA. Photo Credit: (NASA/Paul E. Alers)