Dumbbell Nebula M 27 / NGC 6853
Description : “The Dumbbell Nebula (also known as Apple Core Nebula, Messier 27, M 27, or NGC 6853) is a planetary nebula in the constellation Vulpecula, at a distance of about 1,360 light years.
This object was the first planetary nebula to be discovered; by Charles Messier in 1764. At its brightness of visual magnitude 7.5 and its diameter of about 8 arc-minutes, it is easily visible in binoculars, and a popular observing target in amateur telescopes.
Ring Nebula M 57 / NGC 6720
Description: The Ring Nebula (also catalogued as Messier 57, M57 or NGC 6720) is a planetary nebula in the northern constellation of Lyra. Such objects are formed when a shell of ionized gas is expelled into the surrounding interstellar medium by a red giant star, which was passing through the last stage in its evolution before becoming a white dwarf.
Little Dumbbell Nebula M 76 / NGC 650 – 51
The Little Dumbbell Nebula, also known as Messier 76, NGC 650/651, the Barbell Nebula, or the Cork Nebula, is a planetary nebula in the constellation Perseus. It was discovered by Pierre Méchain in 1780 and included in Charles Messier’s catalogue of comet-like objects as number 76. It was first recognised as a planetary nebula in 1918 by the astronomer Heber Doust Curtis. However, there is some contention to this claim, as Isaac Roberts in 1891 did suggest that M76 might be similar to the Ring Nebula (M57), being instead as seen from the side view. The structure is now classed as a bipolar planetary nebula (BPNe).
Distance to M76 is currently estimated as 780 parsecs or 2,500 light years, making the average dimensions about 0.378 pc. (1.23 ly.) across.
The total nebula shines at the apparent magnitude of +10.1 with its central star or planetary nebula nucleus (PNN) at +15.9v (16.1B) magnitude. The UV-light from the PNN is expanding outer layers that form the present nebula, and has the surface temperature of about 88,400 K. The whole planetary nebula is approaching us at −19.1 km.s−1.
The Little Dumbbell Nebula derives its common name from its resemblance to the Dumbbell Nebula (M27) in Vulpecula. It was originally thought to consist of two separate emission nebulae and was thus given two catalogue numbers in the NGC 650 and 651. Some consider this object to be one of the faintest and hardest to see objects in Messier’s list.
Owl Nebula M 97 / NGC 3587
Description: The Owl Nebula (also known as Messier Object 97 or NGC 3587) is a planetary nebula in the constellation Ursa Major. It was discovered by Pierre Méchain in 1781.
M97 is regarded as one of the more complex of the planetary. The 16th magnitude central star has about 0.7 solar mass and the nebula itself about 0.15 solar mass. The nebula formed roughly 6,000 years ago.
The nebula gets its name from the appearance of owl-like “”eyes”” when viewed through a large (>200 mm) telescope under dark sky conditions with the aid of a so-called “”nebula filter.”” The eyes are also easily visible in photographs of the nebula.