NASA Twitter followers from left; Leigh Checkman (@liprap), Barbara Nixon (@BarbaraNixon), and Beth Schaefer (@boonbeth), hold up signs just before the Astrovan, carrying the STS-134 crew out to launch pad 39a passed by, early Monday, May 16, 2011, at Kennedy Space Center in Cape Canaveral, Fla. During the 16-day mission, Endeavour, with Commander Mark Kelly, Pilot Gregory H. Johnson, Mission Specialists Michael Fincke, Greg Chamitoff, Andrew Feustel and European Space Agency astronaut Robert Vittori will deliver the Alpha Magnetic Spectrometer (AMS) and spare parts including two S-band communications antennas, a high-pressure gas tank and additional spare parts for Dextre. Photo Credit: (NASA/Paul E. Alers)

S70-35595 (18 April 1970) --- President Richard M. Nixon is welcomed to Manned Spacecraft Center (MSC) and introduced by Dr. Thomas O. Paine, Administrator, National Aeronautics and Space Administration (NASA). The First Lady is at extreme left. Others on the speakers platform in this view are Barbara and Jeffrey C. Lovell, children of astronaut James A. Lovell Jr., commander; and Eugene F. Kranz (extreme right), one of four flight directors on duty around the clock during the mission. President Nixon was on the site to present the Presidential Medal of Freedom to the Apollo 13 Mission Operations Team.