It looks uncannily like an eye in the sky, staring back. In fact, this amazing image, captured by the Hubble Space Telescope, shows the planetary nebula NGC 3918, a brilliant cloud of colourful gas in the constellation of Centaurus, around 4,900 light-years from Earth. It’s ‘eyeball’ is actually dying remnants of a red giant star – and is a glimpse of what will one day happen to our own sun.

During the final convulsive phase in the evolution of these stars, huge clouds of gas are ejected from the surface of the star before it emerges from its cocoon as a white dwarf. The intense ultraviolet radiation from the tiny remnant star then causes the surrounding gas to glow like a fluorescent sign. ‘These extraordinary and colourful planetary nebulas are among the most dramatic sights in the night sky, and often have strange and irregular shapes, which are not yet fully explained,’ said NASA.

The powerful jets of gas emerging from the ends of the large structure are estimated to be shooting away from the star at speeds of up to 217,500 miles (350,000 kilometers) per hour. By the standards of astronomical phenomena, planetary nebulas like NGC 3918 are very short-lived, with a lifespan of just a few tens of thousands of years.