NGC 2359, “Thor’s Helmet”, is an unusual type of nebula that surrounds a Wolf-Rayet star.
http://www.astropix.com/ngc2359.html
Click on the link to see a larger version with more information.
This is almost 7 and a half hours of total exposure combining narrowband hydrogen-alpha data with normal RGB.
It’s getting to be the prime season for shooting NGC 2359 as it is now transiting at about 2:30 a.m., which gives you a couple of hours before transit to start shooting it, and a couple of hours after transit to continue shooting before the start of astronomical twilight, at least in the northern hemisphere...
Jerry