Latest results on the composition and structure of the mesosphere and lower thermosphere as measured by CRISTA

The CRISTA experiment (CRyogenic Infrared Spectrometers and Telescopes for the Atmosphere) measured the global distribution of infrared limb emission spectra in the Earth atmosphere during 2 Space Shuttle missions in November 1994 and August 1997. Equipped with three telescopes and four spectrometers and cooled with liquid helium, CRISTA acquires global maps of temperature and atmospheric trace gases with very high horizontal and vertical resolution in the 15-180 km altitude region. This talk will focus on the measurement and retrieval of trace gases in the mesosphere and lower thermosphere, mainly carbon dioxide, ozone and atomic oxygen. These species are of special interest, because they play an important role in the energy budget of the upper atmosphere.