In December last year I wrote a post
about an outwardly insignificant star with a catchy little name: KIC8462852.
This star was emitting a strange light pattern that made scientists operating
the Kepler Space Observatory very excited. It looked as if it was surrounded by
structures that might be artificial.
See here for essential background: http://hpanwo-voice.blogspot.co.uk/2015/12/mysterious-stars-shows-signs-of-life.html.
All stars that have exoplanets change
the way they emit light slightly over time; in fact it is through this method that
exoplanets are often discovered. These changes of light are caused by the exoplanet
transiting or eclipsing the star. This is always in regular periods as the
exoplanet orbits its star in the same way the Earth and other planets do around
the sun. However KIC8462852's light alteration is irregular; this is unheard of
anywhere else in the universe. As I say in the background article, there are
profiles of stars that might indicate the presence of an extraterrestrial
civilization that have been theorized in advance by people like Freeman Dyson.
An irregular light pulse could be a sign of giant artificial megastructures surrounding
the star. Could these observations of KIC8462852 be our first discovery of a
Dyson sphere?
In the initial post I promised an
update as soon as one appeared. The most common "rational
explanation" for KIC8462852's anomalous signature was that it is
surrounded by a disk of comets that had been deposited in its orbit after it
had suffered a near collision with another younger star. Since that proposal
was made Dr Bradley Schaefer of Louisiana
University has cast doubt on it. This is because both he and the
original researcher, Dr Tabetha Boyajian, have gone through astronomical
records of previous observations of KIC8462852 dating back over a century. KIC8462852,
nicknamed "Tabby's Star" after Dr Boyajian, has been slowly dimming.
Between 1890 and 1989 its random pulses have lost twenty percent of their average
intensity. Schaefer worked out that if comets were responsible then over half a
million comets, each a hundred and twenty-five miles across, must have entered
the star's orbit within just a hundred years; impossible. Dr Schaefer does not
accept the alien megastructure theory because he reckons that a Dyson sphere
would not absorb radiation in the visible light part of the electromagnetic
spectrum, but that's just anthropomorphizing. He's essentially saying: "If
I built a megastructure I'd build it only to capture infrared radiation."
How can we put ourselves in the aliens' shoes... apart from the fact they might
not even have two feet like humans do... Maybe he's just scared of being
labelled a loony. However he admits that the effect is probably caused by a
single physical mechanism. Dr Boyajian agrees; "This presents some trouble
for the comet hypothesis." she conceded. A SETI researcher, Doug Vakoch
has announced that a radio-astronomical survey has found no "LGM" or
"Wow!"-like signatures coming from Tabby's Star... or so they've told us. That's
disappointing, but not conclusive. Again, this is anthropomorphizing. We don't
know for certain that ET intelligences would beam organized radio patterns into
space; they might not have the inclination even if they have the technology.
All we know is that we do that. Source: http://finance.yahoo.com/news/bizarre-looking-star-just-got-210900508.html.
So the mystery surrounding KIC8462852 continues and deepens. At the moment it
has become one of the most watched stars in the universe. A plethora of
telescopes are currently focused on it, waiting for its light to dip again. In
the meantime, Dr Boyajian has given a TED Talk, see: https://www.youtube.com/watch?v=R19idXnG8lY.
I've gone off TED, see: http://hpanwo-tv.blogspot.co.uk/2013/03/down-with-skeptocracy.html,
but this one is worth watching. However it's very obvious that Dr Boyajian is
exhibiting the same sense of rational self-preservation as her colleague Dr
Schaefer. They're both only human after all. Her opening remark, before she
even introduces her subject matter is: "Extraordinary
claims require extraordinary evidence, and it is my job, my responsibility as
an astronomer, to remind people that alien hypotheses should always be a last
resort." This means: "I'm
NOT a loony!... Got it!?" As I asked in the first post, why are alien
hypotheses always the last resort? If you want to see KIC8462852 yourself
you'll need at least a five inch telescope. It's an F-type main sequence star, which means it is very similar to the
sun, albeit slightly bigger; but it's a very long way away, almost fifteen
hundred light-years, so its light can't be seen by the naked eye. It is in the
constellation of Cygnus close to the major highly visible stars of Deneb and
Rukh. It's directly northeast of the star cluster NGC 6866.
See here for background:
http://hpanwo-voice.blogspot.co.uk/2015/12/will-tim-peake-see-ufo.html.
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