[ExI] tabby's star dimming again

Tue May 23 16:16:50 UTC 2017

On Tue, May 23, 2017 at 6:25 AM, Stuart LaForge <avant at sollegro.com> wrote:

>
>
>> > 
>> So in a observable universe  27,600,000,000 light years in diameter the
>> only other technological civilization just happens to be only 1480 light
>> years away and Kepler just
>>  
>> happened to find it even though it was looking at 1/400 of the sky and it
>>  
>> just happened to find it when ET had the technological chops to build 5%
>>  
>> of a Dyson Sphere but no more? Doesn't seem very likely. 
>
>
> On the contrary, a combination of the anthropic principle and the theory
>  
> of galactic habitable zones suggests that life would tend to live in
>  
> Goldilocks clusters

Yes, too close to the galactic center and there is too much gamma
radiation from Supernovas and the Supermassive Black Hole, and too far from
the center and there are not enough elements other than Hydrogen and Helium
to support life. But the Galactic goldilocks zone is HUGE, it forms a ring
between 13,000 and 33,000 light years from the center, Earth is 26,000
light years from our Galaxy's center.  And there are at least 200 billion
Galaxies in the observable universe. A planet 1480 light years away is our
next door neighbor

galactically

speaking and even more so cosmically speaking. So I ask again, if ET is
real when we look into the night sky why isn't it obvious that the universe
has been engineered?       

>
> 
> Life became apparent on earth about 4 billion years ago essentially as
>  
> soon as the earth cooled enough from the late heavy bombardment to allowit
> to.

Correct again. On Earth life could not have occurred earlier, it happened
almost as soon as liquid water could exist on the surface, but for all we
know that could of been freakishly early, on other planets it may have
taken much longer.  For intelligence to form on a planet life may have to
start freakishly early, if not their sun might not give Evolution enough
time to produce intelligence before it dies of old age. After all, in the
nearly 4 billion year history of life on this planet Evolution only managed
to come up with a technological civilization once, and it only happened a
few thousand years ago.

> > 
> Then 2.5 billion years ago, about 1.5 billion years after life
>  
> began, cyanobacteria invented photosynthesis. The oxygen made by
>  
> photosynthesis enabled multicellular life which appeared in the fossil
>  
> record about 600 million years ago after about a 1.9 billion year gap.
> Perhaps a brighter star increases the rate of photosynthesis such that the
>  
> gaps between the appearence of photosynthesis and the advent of
>  
> intelligent life are shortened by 50%.

Why? If it's a planet that can support liquid water and its sun is
brighter than ours then it must be further from it's sun than we are from
our sun. So from that planet the disk of the sun would look more intensely
bright than what we see from our planet but it would also look smaller, so
the total amount of solar energy reaching the surface would be the same on
both planets.

>
> 
> How old is Tabby's star?

I don't know, but with 1.43 solar masses if it were as old as our sun it
would be a dead white dwarf by now, or maybe a neutron star.

> 
> What about its companion star the alleged red
>  
> dwarf?

Companion

stars
 may not die together but they are born together, they are of the same age.

 John K Clark
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