The Dumbbell Nebula in Vulpecula really does resemble a dumbbell thru the eyepiece of a moderate or longer focal length telescope (in the summer skies over the Northern Hemisphere). It is known as a planetary nebula (a confusing term, since the nebula has no actual relation to the planets*), and beautifully displays the death throes of a dying (red giant) star, typically of intermediate mass, and too small to result in a supernova. The star sheds its outer energized layers, which glow in different colors — commonly containing emissions in the red (hydrogen alpha) and especially the blue/green (doubled ionized oxygen) portions of the spectrum. The lifespan of a planetary nebula is relatively short by astronomical standards, only a few tens of thousands of years.
Technical details are as follows:
MYHY Observatory summer/fall 2019 – OGS 12.5″ RC; SBIG STL11K; Paramount ME; 1800 sec subs (OIII x 42, binned 2×2; RGB 10 hours/channel, unbinned)
NMS Observatory summer 2007 – RCOS 16″; STL11K; Paramount ME; 1800 subs (Ha x 20, unbinned)
Processed with Maxim, Registar, PixInsight, and Photoshop.
*The 18th century astronomer, William Herschel, who also discovered Uranus, suggested the term “planetary nebula”, since he thought these objects resembled the pale blue green disc of the gas giant.