Tabby star dimming again..Alien megastructure.

For the last few years, a distant star in the constellation Cygnus, known officially as KIC 8462852 and unofficially as Tabby's star or the WTF star, has intrigued astronomers due to its irregular but significant dimming. Astronomers have struggled to find a natural explanation for why the star dims so much, 20 percent, before returning to its regular brightness.

FURTHER READING
Something—we’re not sure what—is radically dimming a star’s light
These observations have led to various hypotheses, including the exotic notion of some kind of alien megastructure passing between the star and Earth-based telescopes. Now the enigmatic star has been observed to be dropping in flux again, and astronomers have put out a call for telescopes around the world to measure light coming from the system
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