| Ring Nebula (M57; NGC 6720) |
| A bright planetary nebula in the constellation Lyra. It has the appearance of a slightly elliptical luminous ring around a central star. The radius is one-third of a light year, and the nebula is 2,000 light years away. If it has always expanded at its current rate of 19 km/s, it is about 5,500 years old. |