A payload canister holds the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere-Shuttle Pallet Satellite-2 (.

A payload canister in the Payload Changeout Room (PCR) at Launch Pad 39A holds the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere-Shuttle Pallet Satellite-2 (CRISTA-SPAS-2) payload for the STS-85 mission (center), as well as the Technology Applications and Science-1 (TAS-1) (top) and International Extreme Ultraviolet Hitchhiker-2 (IEH-2) (bottom) payloads. All three will be transferred from the PCR into the payload bay of the Space Shuttle Orbiter Discovery after the space vehicle arrives at the pad. The CRISTA is a system of three telescopes and four spectrometers to measure infrared radiation emitted by the Earth’s middle atmosphere. During the 11-day mission, the CRISTA-SPAS-2 free-flying satellite will be deployed from Discovery and retrieved later in the flight. Also onboard the satellite will be the Middle Atmosphere High Resolution Spectrograph Investigation (MAHRSI) to measure ultraviolet radiation emitted and scattered by the Earth’s atmosphere. The TAS-1 holds seven separate experiments that will provide data on the Earth’s topography and atmosphere, study the sun’s energy, and test new thermal control devices, as well as several student-developed experiments. The IEH-2 experiments will study ultraviolet radiation from stars, the sun and in the solar system