CRISTA - A Cool Lady from Space

CRyogenic Infrared Spectrometers and Telescopes for the Atmosphere

CRISTA, a scientific instrument to study the earth's atmosphere in the altitude range from 10 km to 150 km, was successfully launched on board NASA's Space Shuttle in November 1994 and in August 1997. CRISTA carried out a three-dimensional survey of the trace gas distributions in the middle and upper atmosphere for ten days on each flight. CRISTA is a remote sensing instrument with three telescopes scanning the atmosphere simultaneously measuring the infrared radiation of more than 15 different trace gases like ozone, CO2, CFCs, nitrous gases, methane, etc.. For this purpose the telescopes and spectrometers of CRISTA are cooled down to a temperature of about - 260 °C by liquid helium.

The focus of attention was the dynamics of the atmosphere, which has a high impact on ozone loss and climate change.

Although the research project is finished in the meantime, CRISTA data are still used for the analysis of dynamical processes in the middle and upper atmosphere.

_{The CRISTA-SPAS satellite is released by the Space Shuttle manipulator arm.}

_{Remote sensing of the atmosphere with three telescopes simultaneously.}