Spaceborne infrared Fourier-transform spectrometers for temperature and humidity sounding of the Earth’s atmosphere

A spaceborne Fourier-transform infrared (FTIR) spectrometer was designed for measuring the spectra of the outgoing Earth’s atmosphere radiation and serves for providing for the needs of online meteorology and climatology with regard to obtaining the following kinds of data: vertical profiles of temperature and humidity profiles in the troposphere and the lower stratosphere, the general and altitudinal ozone distribution, concentrations of small gaseous constituents, temperature of the underlying surface, etc. At present, works are underway at the Keldysh Research Centre for creating IKFS-series FTIR spectrometers for satellites in Sun-synchronous orbits: the IKFS-2 instrument for the Meteor-M spacecraft no. 2 of the Meteor-3M space complex (developed and supplied for testing together with the spacecraft) and an advanced IKFS-3 instrument for the Meteor-MP fourth-generation hydrometeorological and oceanographic space complex for Earth monitoring (at the developmental stage). The composition, functional diagram, and technical specifications of the FTIR spectrometers are presented.