A series of mysterious objects surrounding a giant star millions of miles away could be an alien megastructure, experts believe.
Planet spotters examining data from the Kepler Space Telescope were startled by an unusual light pattern orbiting a star called KIC 8462852.
When they studied the star, which sits some 1,480 light years from Earth, they noticed a swarm of objects surrounding it in an usual pattern.
At first it was thought to be comets, shrapnel from an asteroid impact or even a mistake in the data.
But astronomer Jason Wright from Penn State University offered a more science fiction explanation.
He believes it could be an 'alien megastructure' designed to harness energy from the star.
He said: "Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilization to build."
Tabetha Boyajian oversees Planet Hunters , a program that asked 'citizen scientists' to examine light patterns emitted by stars from their homes.
The post doctoral researcher at Yale says that the light being emitted by KIC 8462852 is what triggered some interest in 2011.
She explained to The Atlantic : "We’d never seen anything like this star.
“It was really weird. We thought it might be bad data or movement on the spacecraft, but everything checked out.”
The light pattern looks like there's a mass of matter surrounding the star.
The Planet Hunters study seeks to explain reasons for it, which include instrument defects, shrapnel from an asteroid belt pileup and an impact of planetary scale.
The final 'natural scenario' it poses is if another star had passed through the KIC 8462852's system, it could have pulled comets inward, but it's far from certain.
Tabetha now admits she is considering extra-terrestrial reasons.
Researchers for SETI - Search for Extra Terrestrial Intelligence - have stated that distant extraterrestrial civilizations may be seen by looking for enormous technological artifacts orbiting other stars.
James and Tabetha are working with Andrew Siemion, the Director of the SETI Research Center at the University of California on a proposal for pointing a radio dish at KIC 8462852.
They hope to see if the radio waves show any signs of technological activity.