ASTRONOMERS HAVE DISCOVERED a previously unknown planet five times the size of Earth – and seemingly made entirely of diamond.

The planet orbits a ‘pulsar’ – a small, burnt-out neutron star – with the catchy name of J1719-1438 some way towards the centre of the Milky Way from us on Earth. It is made up mainly of carbon, and because the planet is so dense scientists believe it must exist in the form of a giant diamond.

“The evolutionary history and amazing density of the planet all suggest it is comprised of carbon – ie a massive diamond,” Matthew Bailes, of Melbourne’s Swinburne University of Technology, said. However, the planet is around 4,000 light years away from Earth, which probably means we won’t be chipping chunks off it any time soon.

According to the New Scientist, the unnamed planet is around 60,000km in diameter – around five times the size of Earth, which is 12,756km across. And yes, it glitters. Travis Metcalfe, of the National Centre for Atmospheric Research in Colorado, told the magazine: “It’s highly speculative, but if you shine a light on it, I can’t see any reason why it wouldn’t sparkle like a diamond.”

Video: Matthew Bailes describes the discovery