The use of IR heterodyne spectroscopy for the study of planetary atmospheres is discussed. Infrared heterodyne spectroscopy provides a convenient and sensitive method for measuring the true intensity profiles of atmospheric spectral lines. Application of radiative transfer theory to measured line shapes can then permit the study of molecular abundances, temperatures, total pressures, excitation conditions, and dynamics of the regions of line formation. The theory of formation of atmospheric spectral lines and the retrieval of the information contained in these molecular lines are illustrated. Notable successes of such retrievals from IR heterodyne measurements on Venus, Mars, Jupiter, and earth are given. A discussion of new developments in IR heterodyne technology is also presented.
Theodor Kostiuk and Michael J. Mumma, "Remote sensing by IR heterodyne spectroscopy," Appl. Opt. 22, 2644-2654 (1983)