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Lyrae. Beta is sometimes also known as Sheliak. Between these two stars, but a trifle nearer to Gamma is where you will find the Ring Nebula. It is about 2,000 light-years from Earth.
As for the true nature of the ring, it is generally believed that sometime in the distant past, a star nearing the end of its life and having used up all of its nuclear fuel hurled great masses of gas out into space in a gaseous shell. This surrounding gas is still expanding and is made visible by the illumination from its extremely hot central star (which is merely the core left from the original star). The surface temperature of the star has been estimated at 216,000 degrees Fahrenheit (120,000 Celsius).
Our own Sun is expected to undergo a similar process in a few billion years.
The Ring Nebula is the most famous and among the brightest examples of what astronomers refer to as planetary nebulae. Despite their name, planetary nebulae have absolutely nothing to do with planets. It is simply because th^y generally appear in tele
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