Planetary nebula. Hubble space telescope image of the M2-9 bipolar planetary nebula, with its 2 pro- minent gas jets. Neutral oxygen is red, singly- ionized nitrogen is green & doubly-ionized oxygen is blue. The jets occur because of a huge ring of gas (not seen here) around the 2 stars at the centre of M2-9. The ring channels gas ejected from the stars at over 320 kilometres per second like the nozzle of a jet engine. M2-9 lies 2100 light years away in the Opiuchus constellation and was formed by a stellar outburst which occurred about 1200 years ago. Image taken by Hubble's Wide Field and Planetary Camera 2 on 2 August 1997.