Planetary nebula. False colour optical image of the 'Spirograph' nebula, IC 418. This is a planetary nebula, formed by the gas thrown off from a dying red giant star. The colours show different gases; ionised nitrogen is red, hydrogen is green and ionised oxygen is blue. The term 'planetary' is misleading, it refers to the similarity of such nebulae to planets in early telescopes. IC 418 lies about 2000 light years from Earth in the constellation Lepus. This image was made using the Wide Field and Planetary Camera 2 (WFPC2) on the Hubble Space Telescope.