M101 Pinwheel Galaxy
M101 is a large spiral galaxy located 21 million light-years from Earth. It has twice as many stars as our Milky Way and stretches 170,000 light-years across. It contains over 1000 star-forming H-II regions which become more visible when using an Ha filter. Four supernovae have been observed in the galaxy, the last one in 2011. The bright blue-green object at the left edge of M101 is ionized region NGC5471, and the fuzzy object further to the left is dwarf galaxy NGC5477. North is at the top.

Scope/Mount: TS-Optics PhotoLine 130mm F7 APO Refractor with Astro-Tech ATREDT30 Focal-Reducer/Field-flattener, Celestron CI-700 Mount
Camera: ZWO ASI1600MMC monochrome with ZWO LRGB filters
Guiding: QHY5L-IIM through Orion Thin OAG, PHD guiding software
Exposure: L (60) 120 sec @ gain=139, ZWO Duo (30) 120 sec @ gain=300, RGB: each channel (10) 120 sec @ gain=200
Software: Nebulosity, PixInsight
Comment: 05-06-2021, Tierra del Sol, CA, good conditions, ZWO Duo filter added to Luminance channel, (LD)RGB.