Water vapor absorption spectra of the upper atmosphere (45-185 cm(-1)).

The far ir nighttime absorption spectrum of the earth's atmosphere above 14 km is determined from observations of the bright moon. The spectra were obtained using a Michelson interferometer attached to a 30-cm telescope aboard a high-altitude jet aircraft. Comparison with a single-layer model atmosphere implies a vertical column of 3.4 +/- 0.4 mum of percipitable water on 30 August 1971 and 2.4 +/- 0.3 mum of precipitable water on 6 January 1972.

Combined effects of a converging beam of light and mirror misalignment in michelson interferometry.

We have derived an expression for the combined effects of a converging beam of light and mirror misalignment on the interferograms obtained with a Michelson interferometer. Each effect has been considered separately by others and leads to symmetric interferograms whose modulation is less than 100%. The combined effect produces an asymmetry in the interferogram as well as a decrease in the modulation. The magnitude of the asymmetric term is given in terms of the optical parameters of the interferometer.