#white dwarf

The very faint planetary nebula, known as Abell 7, is about 1,800 light-years from Earth. It is located just south of Orion toward the constellation Lepus, The Hare. Posing against the Milky Way stars, its simple spherical shape about 8 light-years in diameter is revealed in this deep telescopic image. The beautiful and complex shapes seen within the cosmic cloud are enhanced by emission from hydrogen and oxygen atoms, otherwise it would be much too faint to be appreciated by the eye. A planetary nebula represents a very brief final phase in stellar evolution that our Sun will experience 5 billion years hence, as the nebula's central, once sun-like star loses its outer layers. Abell 7 is estimated to be 20,000 years old, but its central star, seen here as a fading white dwarf, is about 10 billion years old.