New analysis says it ain’t aliens at strange star

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The uncertainty of science: A new analysis of old star data has concluded that KIC 8462852, also known Tabby’s Star and subject to random fluctuations that no scientist can explain, has not dimmed by 20% in the past century.

This reduces the chances that the fluctuations are caused by the slow accumulating construction of a Dyson sphere by an alien civilization, as some have proposed, but it still does nothing to explain the star’s random changes in brightness.


  • mpthompson

    The uncertainty of science indeed. I love this mystery and I hope that it solved within my lifetime. In all likelihood it will turn out to be something prosaic, but there is the slight chance it will be something exotic and completely unexpected. And to think other people twitter their time away wondering what the Kardashians are up to.

  • LocalFluff

    The irregular dimming is obviously a problem with the telescope. It only happened when the telescope was turned in the same way, it turned four times per year to shield from the Sun as it is in heliocentric orbit. There are no astrophysical explanation and the dips don’t even look like transits, even a Dyson sphere can be excluded. This story is just media hype. Poor Tabby who is one of few astronomers to have a star named after her because of a mistake.

    When the long term 20% dimming was proposed this winter, another astronomer quickly wrote a small paper saying there was no dimming. He quckly got reply in both paper and an angry blog post for being mistaken and unknowledgable. During the 100 year period many different photographic plates with different chemicals were used, with different sensitivity for diferent colors and hence for different stars. They are not directly comparable. Also, the plates age differently over time which changes the stars’ brightness. Many different telescopes have been used which also matters, and some have had known defects for which to adjust and whatnot. It is not as easy as it sounds to analyze historic star brigtness.

  • Edward

    Some time back, I read a report that we should be able to find Dyson spheres by the infrared light that they would emit. Has anyone done an IR survey of Tabby?

  • Wayne

    I can’t resist—

    Star Trek Next Gen: “Relics”
    (Dyson Sphere Discovery)

  • mpthompson

    Edward, the Wikipedia article on KIC 8462852 mentions an IR survey was done to eliminate the possibility that the dimming is from large clouds of debris from a planetary collision or from a proto-planetary disk. There is no excess IR energy associated with the star. This would also seem to rule out a megastructure such as a Dyson swarm.

  • LocalFluff

    The lack of IR is also a challenge to the comet tail hypothesis, which would be a very big stretch anyway. The Sun makes up 99% of the mass of the Solar system, Jupiter most of the rest. Comets very very little. That they would cover 20% of the Sun would be fantastic. Tabby, and the large gang of co-authors, should not have gone there, the paper’s refutation of many other potential explanations seems to be quite alright. The only paper I’ve seen that mentions Dyson sphere dismisses it because the dimming don’t look like transits of anything. I think they look like some kind of instrument failure.

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