IRAS 23166 1655

Wallpaper Description:

One of the most perfect geometrical forms created in space, this image shows the formation of an unusual pre-planetary nebula, known as IRAS 23166 1655, around the star LL Pegasi in the constellation of Pegasus. The striking picture shows what appears to be a thin spiral pattern of astonishingly regularity winding around the star, which is itself hidden behind thick dust. The material forming the spiral is moving outwards a speed of about 50 000 km/hour and, by combining this speed with the distance between layers, astronomers calculate that the shells are each separated by about 800 years.

ESA / NASA & R. Sahai