M17 has several names. I grew up reading it referred to as the Swan Nebula but these days the Omega and Checkmark also seem popular but I’m sticking with the “Swan” moniker.
This is one of my favorite visual nebulae and I’ve been looking forward to finally imaging it. As it turns out, though, the Universe has thrown several obstacles in my way over the last month that have kept me from astronomy. About all I was able to do, when I could spare the time for anything and the weather cooperated was to kick of the script and hope for time to look at the results eventually.
Well, eventually is finally here. The happy accident of this is I was able to capture a lot more data than I intended on this. At 48.5 hours this is about double what I was planning. This target didn’t really need that kind of depth but I’m not going to complain having too much data!
This is an emission nebula in Sagittarius and is about 5,000 to 6,000 light years away. Though sources list the nebula at only 12 arcminutes across it is clearly larger as this field of view 1.2 degrees (so maybe that extra integration time didn’t go to waste!).
This is an SHO image (sulfur in red, hydrogen in green and oxygen in blue). For all the technical details, see astrobin.