  We present results of imaging polarimetry of comet 2P/Encke performed on
January 23, 2017 at the heliocentric (1.052 au) and geocentric (1.336 au)
distances and phase angle 46.8 deg, 46 days before perihelion. Observations
were made through the medium-band SED500 ({\lambda}5019/246 {\AA}) and
broadband r-sdss ({\lambda}6200/1200 {\AA}) filters with the multimode focal
reducer SCORPIO-2 at the 6-m BTA telescope of the Special Astrophysical
Observatory (Russia). Dust in comet 2P/Encke was mainly concentrated in the
near-nucleus region of the coma: the maximum dust/gas ratios were 1.5 and 2.9
in the SED500 and the r-sdss filters near the nucleus but dropped sharply to
~0.2 and ~1 at the distance ~2500 km, respectively. Then these ratios began to
increase at distances ~12000 km from the nucleus, the ratio was ~0.3 (SED500)
and ~1.3 (r-sdds). There were significant variations of polarization over the
coma, which correlated with the variations in the dust color and dust/gas
ratio. Changes in polarization and color across the 2P/Encke coma indicate
changes in physical properties of the dust particles with the distance from the
nucleus. Our Sh-matrix computer simulations of light scattering by Gaussian
particles allow us to suggest that the observed trends in color and
polarization are mainly result from changing particle size.
