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In planetary research, Fourier transform infrared spectrometers (FTIR) solve a number of important scientific goals related both to the atmosphere and to the surface sounding. For remote orbital measurements, these goals are the thermal sounding of the atmosphere using, in particular, the 15-µm CO2 band, sensitive detections of minor gaseous species and aerosol characterization. FTIR can address similar atmospheric science goals when observing from a planetary surface allowing for better-resolved boundary layer and achieving greater accuracy (longer integration) for minor species detection. For studies of planetary surfaces, characterization of mineralogical composition in a wide IR range including sensitive measurements of hydration of the soil on airless bodies can be done. We outline a family of FTIR instruments dedicated to studies of Mars and the Moon. TIRVIM is a channel of ACS on ExoMars TGO (in orbit around Mars since October 2016). It is a 2-inch interferometer for nadir and solar occultation measurements of Mars’ atmosphere. It covers a spectral range of 1.7–17 µm with spectral resolution up to 0.13 cm−1. LUMIS is a similar instrument for Luna-Resource Orbiter (Luna-26) Roscosmos mission dedicated to the search for hydration of the lunar regolith in the 6-µm band. The spectral range of LUMIS is broad (1.7–17 µm), but its sensitivity is optimized for the 4–8 µm region. The spectral resolution is 50 cm−1. We also describe recent developments focused on technical solutions for miniaturized FTIR instruments with a very high spectral resolution (0.05 cm−1 and higher). The prototype targets measurements of minor atmospheric species from the surface of Mars using the Sun tracking. One important task is to provide a high precision of interferometer’s mirror movement. Another task is the development of a precise two-coordinate mechanism to seek for and follow the Sun.

Fourier-spectrometer TIRVIM is a part of ACS spectral complex aboard Mars-Express orbiter spacecraft. TIRVIM spectral range is 2–16 micron. It can operate as a spectrometer – with the Sun as a standard radiation source (“occultation” mode) or as a spectro-radiometer (“nadir” mode). In occultation mode the spectral resolution is 0.2 cm-1, in nadir mode – 1.3 cm-1. The main scientific objective of the occultation mode is to search for atmosphere minor constituents, of the nadir mode – to monitor the Mars atmosphere vertical thermal profile (by 15-micron CO2 band). The occultation mode is self-calibrated. For absolute calibration in the nadir mode TIRVIM has a rotating inlet flat mirror (single-axis foreoptic) able to point the FOV (2o) to nadir, space, built-in black-body or to another direction in the plane. TIRVIM mass is 12 kg, the power consumption is 15 W.

The gel-to-glass transition in SiO 2 xerogels prepared by inorganic sol-gel synthesis was studied. The evolution of the molecular structure is traced using the infrared and low-frequency Raman spectroscopy methods. The elastic moduli of the samples as well as the pore wall moduli at various stages of heat treatment are determined from the data on Brillouin scattering. The formation of monolithic glass on the macroscopic level manifests itself within a narrow temperature range by the dramatic increase of Young's modulus to the accepted value for fused silica. This phenomenon coincides with structural transformations on the molecular scale: (i) the definite correlation radius (the long-range order sphere) appears; (ii) local distortions of the silica network relax.