Binary deathstar has Earth in its sights

A spectacular, rotating binary star system is a ticking time bomb, ready to throw out a searing beam of high-energy gamma rays - and Earth may be right in the line of fire.

"Viewed from Earth, the rotating tail appears to be laid out on the sky in an almost perfect spiral. It could only appear like that if we are looking nearly exactly down on the axis of the binary system," said Tuthill.

This means we are peering down the barrel of the gun, as when binary supernovae go off, all their energy is focussed into a narrow beam of wildly destructive gamma ray radiation that emanates (both up and down) from the poles of the system.

Though the risk may be remote, there is evidence that gamma ray bursts have swept over the planet at various points in Earth's history with a devastating effect on life.