Arms Wide Open

This image of Messier 101, the Pinwheel Galaxy, is the result of 32 hours of integration under dark skies, using a dual-telescope setup to make the most of short summer nights. I used the ARTEC 250 Newtonian for RGB stars the emission regions the C11 EdgeHD for luminance.

M101 is a classic Sc-type spiral galaxy located about 21 million light-years away in Ursa Major. It spans over 170,000 light-years — larger than the Milky Way — and features dozens of prominent H II regions, some of which are visible here as pink knots scattered along the spiral arms.