The Ring Nebula also catalogued as Messier 57, M57 and NGC 6720 is a planetary nebula in the norther

The Ring Nebula (also catalogued as Messier 57, M57 and NGC 6720) is a planetary nebula in the northern constellation of Lyra. Such a nebula is formed when a star, during the last stages of its evolution before becoming a white dwarf, expels a vast luminous envelope of ionized gas into the surrounding interstellar space.






Messier 57 is found south of the bright star Vega, which forms the northwestern vertex of the Summer Triangle asterism. The nebula lies about 40% of the distance from Beta (β) to Gamma (γ) Lyrae, making it an easy target for amateur astronomers to find.

M57, or the Ring Nebula, is a planetary nebula, the glowing remains of a sun-like star. The tiny white dot in the center of the nebula is the star’s hot core, called a white dwarf. M57 is about 2,000 light-years away in the constellation Lyra, and is best observed during August. Discovered by the French astronomer Antoine Darquier de Pellepoix in 1779, the Ring Nebula has an apparent magnitude of 8.8 and can be spotted with moderately sized telescopes.

M57 is tilted toward Earth so that astronomers see the ring face-on. This gorgeous, high-resolution Hubble image helped astronomers determine that the nebula’s shape is more complicated than initially thought. The blue gas in the nebula’s center is actually a football-shaped structure seen end-on that pierces the red, doughnut-shaped material. The inner rim of the ring displays an intricate structure of dark, irregular knots of dense gas that the stellar winds have not yet been able to blow away. The knots and their tails look like spokes.