Astronaut Pam Melroy presents a commemorative collage of photos and items flown aboard space shuttle Discovery to Bob Cabana, director of NASA's Stennis Space Center in South Mississippi. Melroy commanded NASA's space shuttle mission STS-120. She and fellow crewmembers (from left) Doug Wheelock, Stephanie Wilson, George Zamka, Scott Parazynski and Paolo Nespoli visited Stennis Dec. 13, 2007, to thank employees for the reliability and safe performance of the space shuttle's main engines, which on Oct. 23 launched them aboard Discovery on their mission to the International Space Station.
