The Triangulum Galaxy
This is a spiral galaxy about 3 million light years away and at 73×45 arc minutes it appears relatively large in our sky. It is in fact the 3rd largest galaxy in our local group, with a visual brightness of mag 5.7.
Image Data UHC filtered
Focal Length 500mm
Focal Ratio f4
Exposure 3 hrs 35 mins
Blog Post(old)
Worldwide Telescope Link