Fluctuations in light from star KIC 8462852

[Mark_Heli]

There is an interesting article in todays newspaper about random fluctuations in the light coming from star KIC 8462852 which does not have an explanation.

http://www.news.com.au/technology/science/space/comets-cannot-explain-kic-8462852s-strange-stuttering-light/news-story/1267c7a77e51b96090710da6cc4a9d4a

This was discovered by the amateur Planet Hunters project and has been followed up SETI.

One explanation that was initially proposed was that the fluctuations were caused by a swarm of comets heading towards the star, however this now seems to have been discounted by a professor at Louisiana State University.

It has also been proposed that these fluctuations could be caused by a speculative idea called a Dyson Sphere - a structure built around a star by an advanced civilisation to harness the power from the star.

It would interesting to hear if anyone on the forum has idea's about what might be causing this.

Cheers,
Mark

[rustigsmed]

yep interesting alright

http://arxiv.org/abs/1601.03256

[AussieTrooper]

"Within the context of the comet-family idea, the century-long dimming trend requires an estimated 648,000 giant comets (each with 200 km diameter) all orchestrated to pass in front of the star within the last century."

As long as none of these hit the earth and killed us all (which one almost certainly would), then it would be a fantastic sight.

Most likely this is caused by something else entirely.

[middy]

Maybe an advanced civilisation has worked out how to control their star's output and are using it to send a signal. Heaps more power than you could ever generate, and right on your "doorstep". Like a big-arse lighthouse; easily seen from all over the galaxy. :shrug:

[AussieTrooper]

Any civilisation capable of doing that should easily be able to detect us too.

[Mark_Heli]

This is in the news again this morning...

http://www.news.com.au/technology/science/space/alien-megastructure-flickering-star-kic-8463853-wont-give-up-its-dark-secret/news-story/31bee8a46d5b177858dc4a1ad020e403

Certainly an interesting mystery.

[markbakovic]

Yeah it's unfortunate that Kepler went bad and the 7xx day apparent period meant only 2 passes of "the object(s)" were captured properly. Especially because some irregular (disintegrating?) occulter(s) not in orbit around tabbys star would seem to be a good fit, that would then be expected to affect nearby stars in similar ways eventually. It seems like that's what the new papers authors investigated, but without the same precision as available in the original run... there's a lot of uncertainty in drawing conclusions one way or the other. It may wind up another "Wow!" signal...

I think it should be noted that the comet swarm hypothesis is somewhat misrepresented as being strongly promoted by Boyajian et al in this paper and a lot of the popsci articles including news.com.au's when it was much more of "the only one not conclusively ruled out straight away apart from Omg It's Aliens!". They had to propose some kind of explanation...

[Mark_Heli]

Looks like scientists at the Max Plank Institute have found another star (EPIC 204278916) which is showing large fluctuations of light... Very interesting.

http://www.news.com.au/technology/science/space/a-second-dyson-sphere-star-epic-204278916-shows-strange-flickering-of-up-to-65-per-cent/news-story/e51b9c2afaaf9045edd3bfbabc23850f

Cheers,
Mark

[Mark_Heli]

Looks like the star's brightness has been observed to be dipping again over the past few days.

http://www.news.com.au/technology/science/space/this-is-not-a-drill-scientists-scramble-to-observe-mysterious-tabbys-star/news-story/2da6e5dbac7a5c72b7caed20cb268acb

Any suggestions for what may be causing it?

Cheers,
Mark

[astroron]

Answer me this:question:
If a civilization could capture the energy of a star, then piloting a craft across the galaxy would be child's play
It seems mind boggling that they would use such energy to send a message across astronomical distances in the hope of contacting some hypothesized
civilization that they wouldn't know even exists.
I find it pretty poor science for these "scientist" to put forward in my opinion outlandish claims/ideas with this Dyson Sphere.
Because something doesn't fit the the current theory of star formation etc, doesn't give them the right to put out such nonsense.
An example of not knowing "everything" about star formation is the Supernova 1987A, up until this supernova exploded it was always thought that type 2 Supernovae came from Red Giant stars.
Sanduleak -69° 202 was a Blue Super giant star.
It changed the way astrophysicists thought about the revolution of star formation and of course their deaths.
Science still has a long way to go before it can explain everything to do with peculiarities of star formation.
End of rant
Cheers:thumbsup:

[AussieTrooper]

New kind of variable star.