(11/07/2001) -- Under the watchful eyes of a trainer at SPACEHAB, Cape Canaveral, Fla., STS-107 Mission Specialist Laurel Clark checks out a glove box experiment for the June 2002 mission. STS-107 has two payload elements, the Double Module in its first flight into space and a Hitchhiker payload. The experiments range from material sciences to life sciences (many rats). The Hitchhiker carrier system is modular and expandable in accordance with payload requirements. Hitchhiker experiments are housed in canisters or attached to mounting plates. The Hitchhiker canister comes in two varieties--the Hitchhiker Motorized Door Canister and the Sealed Canisters