M27

From South Dublin Astronomical Society

M27
Type	Planetary nebula
NGC	NGC 6853
Constellation	Vulpecula
Right Ascension	19h 59.6m
Declination	+22° 43’
Magnitude	7.4
Size	8 x 5.7 arc min.
Photo from Dave Grennan http://webtreatz.com

The Dumbbell nebula, or M27, is considered to be one of the best planetary nebulae for binocular observers. Planetary nebulae are the outer layers shed by stars near the end of their life cycle. At this phase in their life, such stars may lose up to half their original mass. Strong stellar winds blowing from their surface shock previously ejected material and the high-energy radiation causes these shells to glow. M27 is in the same binocular field as Gamma Sagittae and shows as a lovely puff of light set in an attractive star field. With larger binoculars you may see a hint of the “applecore” shape of the nebula — certainly, the centre appears a little more “pinched”. Scan about 4° west of M27 and you’ll spy a chain of stars more than 5° long running northeast to the southwest — broken in places but the eye still sees it as a continuous thread. Has anyone noticed this asterism before?