Sen. John F. Kerry (center), D-Mass., discusses Space Shuttle processing with NASA Vehicle Manager Stephanie Stilson during a tour of the Orbiter Processing Facility (OPF). They are standing under the orbiter Discovery, which is being prepared for flight on the next Space Shuttle mission. The tour follows a public meeting Kerry held at the Dr. Kurt H. Debus Conference Facility at the Kennedy Space Center Visitor Complex. He said he chose to speak at KSC because it symbolizes America’s commitment to science, innovation and technology. He and Sen. John Edwards, D-N.C., are on a speaking tour prior to their appearance at the Democratic National Convention in Boston.