New data from Tabby’s Star suggests that dust, not alien megastructures, is the cause of its dimming

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New observations of Tabby’s Star now suggests that it is dust, not alien megastructures, that has caused the star’s erratic fluctuations in dimming over the past century.

“Dust is most likely the reason why the star’s light appears to dim and brighten. The new data shows that different colors of light are being blocked at different intensities. Therefore, whatever is passing between us and the star is not opaque, as would be expected from a planet or alien megastructure,” said [LSU Department of Physics & Astronomy Assistant Professor Tabetha Boyajian].

Though the data appears strong, it still leaves astronomers a bit baffled about how dust could cause the particular dimming they have seen.


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  • Localfluff

    It must be a very particular dust cloud to dim a star which is even larger than the Sun. That’s according to truly *stellar* physics that classifies these nearly Sun-like F-stars by the millions. The dimmings have been up to 20% almost from one day to another. The radius of the Sun is about 4 times the distance to the Moon. You don’t cover that up very easily. North Koreans covering up their Pyongyang central Square with flags all at once doesn’t quite do it. Even the trees reddening in the autumn are too slow. What could suddenly and repeatedly cover up an entire star?

    And it only happened to one in 100,000 observed by the same telescope. If one dust cloud once dimmed a star, sure that must happen sometime. But this guy is regular with its irregular dimmings. I thought there was something wrong with the telescope, but it seems very well confirmed form the ground now. So even the bad ideas don’t work. That’s what exploration is all about. This beats our brains, and the human instinct is to look closer until we beat it back. Our brain cells somehow conspire against these unknown thingies to make up ideas about them that, seemingly, neutralizes them to our comfort world. That got a bit philosopsychical.

  • LocalFluff: Heh. Excellent post. Made me laugh, and was scientifically thoughtful as well.

  • Mike Fortner

    I know we have heard a lot about a Dyson sphere. I agree with Localfluff. Dust seems unlikely. My vote is for a Larry Niven Ring world structure. There were analyzed as being unstable so it could be just the ticket. The ring could just revolve around the star in a very unpredictable manner. Just a thought. This is fun too.

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