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Searching for Neighbors III

November 9, 2016

Kepler space telescope has revealed an amazing array of planets in other star systems. But what may be its most intriguing discovery isn’t a planet at all. In fact, scientists still aren’t certain just what it is.

It’s in a star system known as Tabby’s Star, after the leader of the team that studied it, Tabetha Boyajian.

Kepler discovers a planet by watching it “transit” in front of its star, blocking a small fraction of the star’s light — usually no more than one percent. But the light from Tabby’s Star dipped by as much as 22 percent. And there were many other drops that weren’t as deep, but that lasted for days instead of the hours required for most planet transits. Boyajian’s team wrote that the dips could be produced by a swarm of dusty comets in a lopsided orbit around the star.

One other possible explanation, though, is massive structures built by a super-civilization. Such structures could be designed to capture the star’s light to power the civilization.

Follow-up observations by other telescopes haven’t found anything to support that idea. There’s no infrared glow, which would be generated as the structures heated up. And there’s no evidence of radio transmissions from the system.

But the comet idea doesn’t work especially well, either — there’s no evidence of such swarms in any other star systems, for example. So the nature of Tabby’s Star is still a mystery.

More about the search for other civilizations tomorrow.

Script by Damond Benningfield

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