KIC 8462852 sounds like an ordinary name for a star. But this one, 1,500 light years from our earth, has Nasa astronomers excited because it shows unusual behaviour which could potentially be explained by alien activity.
Nasa’s Kepler Space Telescope, the eye in the sky that looks for earth-sized planets, noticed the star was showing an extraordinary dip in light at irregular intervals. While all the 150,000 stars monitored by it so far had about a 2% dip in light when their planets pass in front, KIC 8462852 was showing a 20% dip – meaning the cause was not a planet, astronomer Stuart Clark wrote in The Guardian.
Kepler watched the star for more than four years and scientists made doubly sure the telescope was functioning fine when it collected the data. Scientist Tabetha Boyajian of Yale University, who initially studied it, offered natural scenarios like a “swarm of comets” as a safe explanation.
But others, like Jason Wright from the Penn state university who is working with her, suggested an alternative scenario: A “swarm of megastructures”.
“Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilisation to build. I was fascinated by how crazy it looked,” Wright wrote on his website.
His word of caution was, however, lost, as the finding, which was first reported on the Atlantic website, has now gone viral.
Tabby’s Star, WTF star
Skywatchers in the northern hemisphere are familiar with these two constellations on the plane of the Milky Way – Cygnus, which looks like a swan in full flight, and Lyra, which has the shape of a Greek harp.
Between these two constellations sits the unusual star KIC 8462852, invisible to the naked eye. It was spotted first by users on the online astronomy crowd-sourcing interface Planet Hunters, which scans publicly available data from Kepler telescope for earth-like planets
In 2011, citizen astronomers noticed the peculiar light pattern, and when they couldn’t make sense of it, they sent it to the group’s advisory science team that includes Boyajian.
She published an academic paper last month, concluding it could be because of a “swarm of comets” but Wright found the explanation “contrived” and is now set to publish his own findings.
Wright calls it “Tabby’s Star”. His team calls it the “WTF star” after the subtitle to Boyajian’s paper, “Where’s the flux?”
Watch | Kepler, the space observatory by NASA discovers Earth-like planets orbiting stars
Megastructures by aliens?
What exactly are the “megastructures” that the astronomers are talking about, and what kind of civilisations can build them?
On his website, Wright mulled over the possibility of a swarm of “Dyson spheres”, hypothetical planet-like structures that highly advanced civilisations can build to tap most of the energy from a star.
Spoiler alert. We are now going into the realm of science fiction
The term was first described by British science fiction writer Olaf Stapledon in his book, Star Maker. He described it as a megastructure that completely encompasses a star and captures most of its power output. The idea was taken up and popularised by American theoretical physicist Freeman Dyson. He speculated that highly technological civilisations would need so much energy that they would have to build such massive energy tappers around their star. Dyson gave his name to the concept.
“One of the things that occurred to me is that a civilisation that would build one megastructure would eventually build more. The star might be surrounded by them (a Dyson swarm). What would that look like?” Wright wrote.
Wright and Boyajian are now working with Andrew Siemion, the director of the SETI Research Center at the University of California, to look for radio evidence. SETI, short for Search for Extraterrestrial Intelligence, is the collective name for scientific activities undertaken to search for intelligent alien life.
CNN reported the trio has submitted a series of proposals to use telescopes, including the premier Green Bank Telescope to look deeper into the anomaly. The results of the study could be out as early as next year.