An infrared meridional spectrometer MIRS intended for studying the spectral composition and spatial distribution of nightglows and auroras is described. The spectrometer allows spectral imaging of the vertical circle of a celestial hemisphere in the 730–900 nm wavelength range with a spectral resolution of about 0.7 nm and a rate of 4 frames/min. The device has been designed in a field version at the Polar Geophysical Institute of the Kola Science Center RAS in 2008 and is operable under any weather conditions. The optical circuit has a classical design with a transmission grating. During the winter observation season 2008/2009 the spectrometer operated at the Cap Heer observatory of the Polar Geophysical Institute (arch. Spitsbergen). The observational results have shown that the spectrometer is a useful tool for studying auroras and nightglows; when combined with an all-sky camera, it provides a view of a general auroral situation.