The region immediately NW of the Swan Nebula (M17), part of which is seen very brightly at bottom right.
Green: H-alpha, 7 hrs unbinned; Blue: OIII 7 hrs 2x2; Red: SII 7 hrs 2x2, all in 1 hr subs.
You can see that while the Swan is bright blue and hence relatively rich in OIII, the Cygnet, as we have called it, is much fainter, but relatively rich in SII, suggesting (just a guess) old regurgitated star-guts from past supernovas. The head (with a bright star for an eye) is facing to our right, long neck almost vertical, slightly more blue hints on the chest, then wings held out cormorant-style either side. There is much thick black dust between the Cygnet and the Swan.
Aspen CG16M with 3nM filters. PlaneWave 20 inch scope.
North is on the left. 0.55 sec arc/pixel. Field approx 0.5 degrees.
