SNR G65.3+5.7 is a huge remnant shell following the explosion of a star.
It is estimated to be 230 light years in diameter. For comparison,
the more famous Veil nebula is about 100 light years across.
This image is perhaps my most ambitious project in 20 years of astrophotography. Not only is the nebula extremely faint, it is so large that it needed to be a 6 panel mosaic taken with two telescopes and cameras in a tandem arrangement. I spent all the clear nights in the summer collecting data.
Total integration time:
176 hours (about 30hrs per panel)