Astronomical measurements at mid- and far-infrared wavelengths can be made by using aircraft or balloons to carry telescopes above the strongly absorbing lower atmosphere. To measure the atmospheric background radiation present at these altitudes, a Michelson interferometer has been built and flown to a height of 38 km on a balloon. This paper describes the instrument and the methods of data reduction and calibration, and presents initial spectra in the range 100–1000 cm−1 (10–100 μ) obtained to a mean resolution of 34 cm−1 during flight.
R. E. Jennings and A. F. M. Moorwood, "Atmospheric Emission Measurements with a Balloon-Borne Michelson Interferometer," Appl. Opt. 10, 2311-2318 (1971)