A 2 hour exposure thru Kopernik Observatory's 20-inch telescope using an SBIG STL-1301E CCD camera.
Messier: (Oct. 21st, 1780) "Nebula on the right foot of Andromeda, seen by M. Mechain 5th Sept. 1780. On the 21st Oct. following, M. Messier looked for it with his achromatic telescope and it seemed to him that it comprised only small stars containing nebulosity and that the least light employed to illuminate the micrometer wires caused it to disappear. The position was determined from the star phi Andromedae, 4th mag. Diam. 2'."
W. Herschel: Thought it to be an unresolvable double nebula, hence the two NGC numbers. (651 represents the northern part.).
Webb: "Pearly-white nebula; double; curious miniature of M-27 and, like it, gaseous: (west part is) a little brighter."
M-76 is a faint Planetary Nebula located in the extreme western portion of the constellation Perseus. It is sometimes called the "Little Dumbbell" (see M-27, the Dumbbell Nebula). In small telescopes it appears as a roughly rectangular or box-shaped mass measuring about 2' x 1'. However, as can be seen in the Kopernik CCD image, this central mass is surrounded buy great arcs or nebulous filaments of gas.
The central star (old stellar core) has a surface temperature of about 60,000K. Distances to planetary nebulae are difficult to determine. Rough estimates for M-76’s distance range from 1,750 light years all the way to 8,200 light years. If it is at the lower distance the actual diameter of the nebula would be about 1 light year.
For more about Planetary Nebulae, including additional links, click here.
George Normandin, KAS
February 1st, 2012