  The paper describes the study of field of scattered radiation in the
mesosphere basing on wide-angle polarization camera (WAPC) measurements of the
twilight sky background. Mid-August observations in 2012 and 2013 show the
decrease of single scattering polarization value that can be related with
Perseids meteor dust moderation in the upper mesosphere. Effect correlates with
activity of tiny fraction of Perseids shower. Polarization and temperature
analysis allows estimating the altitude of dust layer and character
polarization of dust scattering.
