Cat's eye planetary nebula (NGC 6543). A planetary nebula is a glowing shell of gas cast off by a Sun-like star near the end of its life. Radiation from the exposed core of the star ionises the gas in the shell, causing it to emit light. They are short lived objects, lasting only around 10,000 years before the central star cools and loses the energy required to ionise the gas, which causes it to fade. This planetary nebula lies 3300 light years from Earth in the constellation Draco. Image obtained by the West Mountain Observatory, Utah, USA.