An Infrared Determination of the Reddening and Distance to Dwingeloo 1

Abstract

We present for the first time infrared observations of the nearby highly obscured galaxy Dwingeloo 1 (Dw1), including deep H-band imaging covering a total of 4.9x4.9 arcmin, together with J and Ks imaging of the central 2.5x2.5 arcmin. We used the small dispersion of the intrinsic infrared colors of spiral galaxies to determine an infrared H-band extinction of A_H = 0.47+/-0.11 mag towards Dw1. In using infrared colors, the uncertainties in the reddening and distance are reduced by a factor of three. The H-band magnitude corrected for extinction and the infrared Tully-Fisher relation are then used to estimate a distance modulus of (m-M)_0 = 28.62+/-0.27, and thus a distance of d = 5.3 {+0.7/-0.6} Mpc, which puts Dw1 at the far end of the IC342/Maffei 1 & 2 group. Our result is largely independent of the nature of the reddening law because we estimated both the reddening and the distance at the same wavelength range.