Mesosphere Study by Wide-Field Twilight Polarization Measurements: First Results beyond the Polar Circle

The paper describes the observations and first results of studying the mesosphere temperature and dust based on twilight wide-field polarization analysis using original all-sky camera started in 2015 in Apatity, northern Russia (67.6 deg N, 33.4 deg E). It is the first twilight polarization measurements session conducted in the polar region and the first measurements during the winter and early spring season. The general polarization properties of twilight sky and the separation procedure of single scattering are described. The Boltzmann temperature decrease above 70 km and lack of mesosphere dust that is typical for this season are the key results of the study.