The cats eye Nebula.

Image Credit: X-ray: NASA/CXC/SAO; Optical: NASA/STScI

This image is a composite of data from NASA's Chandra X-ray Observatory and the Hubble Space Telescope. It shows the Cats eye nebula in the constellation of Draco some 3000 light years from earth. The Cat's Eye Nebula is one of the most complex planetary nebulae ever seen by astronomers.

The picture, half a light year across, shows a sun, at the centre of the nebula, in its final stages. As the sun runs out if fuel it enters a planetary nebula phase, throwing off its outer layers in a series of violent explosive events. The material shed by the star is flying away at a speed of about 4 million miles per hour. Calculations indicate that the central star currently weighs just over one solar mass, but that it had an initial mass of around 5 solar masses prior to its nebular transformation.