This is an update in my continuing coverage of KIC 8462852, or Boyajian’s star for September
10, 2017.
Check out the dedicated playlist for this enigmatic star on this channel for the back
story.
First, the emergent news.
The star has been dipping regularly over the last few months, but now we have something
different happening.
As of a few nights ago, the star basically has gone into free fall and is on its way
down to what appears, though you can never be sure with this star, to be a major dipping
event, the first of its type since ground observations of the star commenced.
In the past, these dips occasionally got very deep in the Kepler light curve, as much as
22 percent.
This one is somewhere between 2.5 to 3 percent as of last night and shows no signs of recovery,
so may go significantly lower, we shall see.
These types of major dimming events are among the most interesting things this star does,
because to block that kind of light you need truly massive objects or structures of objects
to do it, in this case several times the size of Jupiter.
In the description below, I have placed three links.
The first is to the official website of the science team investigating the star, though
there are a whole lot of people looking at this one.
In the blog section of that site, you’ll find daily updates of the light curves of
the star posted by Dr. Boyajian should you wish to monitor it in real time.
These are taken by two separate observatories each night, both in different areas of the
globe.
The funding for time on these telescopes was originally crowd sourced on Kickstarter, but
that was a while ago so the second link is to Dr. Boyajian’s donations page.
I would encourage anyone interested in this star to consider a donation so study of this
star with active, nightly photometric observations can continue.
The third link is to a new paper by F. Keifer and colleagues.
In it they detail a correlation between two features in the Kepler light curve that might
suggest the passage of the same object, specifically a string of exocomets passing in front of
the star with a period of just over 928 days.
They also point out that this could also be consistent with the recent hypothesis that
the dimming is due to a planet with a massive ring system.
The paper goes on to make a prediction that these exocomets will pass again in October
of 2019.
As usual, both of these possibilities have problems however.
In regards to exocomets, there are two.
Firstly is Bradley Schaeffer’s calculation that to cause this effect, along with the
long term variability of the star, you would need a perhaps implausible number of comets
orchestrated to pass in front of the star over a long period of time.
The other problem is the paper by S. Rapport and colleagues from a few weeks ago which
made the case that exocomet transits in the Kepler light curve simply do not look like
the dips at KIC 8462852.
With the planetary ring hypothesis, the problem there is stability and how long such a ring
would last.
This is unclear, but it may be the case that such a ring would not last long in geologic
time and the chances of just happening to catch it while it was there are somewhat bad.
Then again, whatever this is, it’s probably safe to say that it’s a rare phenomenon
regardless of the cause since we do not see other examples of this star’s behavior.
At least not yet.
One the things scientists will do in the future when trying to figure out what’s going on
with this star is to search for other examples of the phenomenon.
If none are found, and problems continue to plague any of the explanations out there,
then other possibilities will need to be considered including options related to SETI, but those
too come with problems.
Thanks for listening!
I am futurist and science fiction author John Michael Godier currently wondering about the
snickering aliens again.
What would happen if we got a radio signal from Tabby’s star that when translated came
out to “Fooled you!” and whole thing was the alien equivalent of a whoopee cushion
and be sure check out my books at your favorite online book retailer and subscribe to my channel
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