Messier 57 (M57)

Common Name: Ring Nebula

Also Known as: NGC 6720

Object Type: Planetary Nebula

Constellation: Lyra

Distance from Earth: 2,300 light years

Apparent Magnitude: 8.8

Coordinates: RA 18H 53M 30.079S DEC 33 deg 01 min 45.03 sec

Actual Size: 2.6 light years in diameter

Apparent Dimensions: nebula disk angular size is 1.5 arc-minutes x 1 arc-minutes

Discovered by: M57 was discovered by Antoine Darquier Pellepoix in January 1779. Charles Messier independently discovered the object on January 31, 1779.

Description: : The Ring Nebula is one of only 4 planetary nebulae listed in the Messier catalog.
Planetary nebulae are formed when a dying red giant star expels its shell of ionized gas to form the nebula, while the star itself becomes a white dwarf, a dense stellar remnant roughly the size of the Earth.
The central planetary nebula nucleus (PNN) has an estimated mass of 0.61 to 0.62 solar masses and a surface temperature of about 125,000 K. It is about 200 times more luminous than the Sun.
The central star of the Ring Nebula ejected its outer layers 6,000 to 8,000 years ago and they have since expanded over an area about 1.3 light years in radius.
The nebula is expanding at a rate of about 1 arc second per century, which corresponds to a velocity of 20 to 30 km/s.
It is classified as a bi-polar as it has thick equatorial rings that extend its structure through its main axis.
The nebula’s ring shape appears in different colors and the different layers seen in images are not equally bright.
This is because they consist of different layers of the central star, or different elements at different temperatures.
The outermost layer, which appears red in images, consists almost entirely of hydrogen.
Elements that appear in different colors include doubly-ionized oxygen, molecular nitrogen, molecular sulfur, and helium.

Click Below Image(s) for Full Size:

The nebula cannot be resolved in small binoculars. Small telescopes will reveal the nebula’s ring shape.
It is best seen in scopes 8 inches or larger.

The best time of year to observe M57 is the summer months of June-August.

Platesolve

M57 Planetary Nebula

Imaging Details
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