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The merged and improved (?) KIC 8462852 thread

QUOTE={ Emma Snow };11404298]Upon further reflection I think this thread needs a break so that it can relax a little and have a coffee. Sojourner and Dryson, you might both want to reconsider your tone.
Dryson, don't start a new thread about this.

Dryson said:
And no I will continue to use KIC to refer to Tabby's Star.

This is an asinine statement because it doesn't identify the star at all. I have updated the thread title to make more sense. Thanks for pointing it out, Asbo Zaprudder.[/QUOTE]

The entire topic is about KIC 8462852. We are not talking about any other stars so using KIC in the context of relating to KIC 8462852 is in fact correct.
I have been using Planer Hunter the last few days to learn about transits around stars. It is rather interesting to take part in the search.

What I have learned so fad is that planets the size of Earth will mostly reside in what is called the noise or the points where all of the fluctuations of the star take place. Locating an Earth sized resides around the .001% (.999) size comparison. A plant like Neptune which is smaller than Jupiter would reside around the .002% (.998) on the percentage chart with a planet like Jupiter residing at around the 1% (.9990) comparison

http://blog.planethunters.org/2010/12/20/transiting-planets/

Jupiter is approx. 6.69% the diameter of KIC and causes a 1% dim to occur.

15% the diameter of KIC is 313,200 km in diameter but only creates a 3% to 4% ddim based on the size comparisons between Jupiter. Doubling the diameter puts us at 8% and 616,400 km in diameter. 12% puts us 929,600 km in dia.

Tabby's Star is 2.088 mil million in diameter which we are approaching half the diameter of at 15%. So how is it possible for a planet or gas giant nearly half the diameter of KIC to even exist?

If the object was a star it would have certaintly have shown up as a transiting star.

The events could have been sun spots though.
 
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So how is it possible for a planet or gas giant nearly half the diameter of KIC to even exist?
I'm at a loss to understand why you continue to believe a spheroidal body is the cause of the dips seen in the light output from KIC 8462852.

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So how is it possible for a planet or gas giant nearly half the diameter of KIC to even exist?
I'm at a loss to understand why you continue to believe a spheroidal body is the cause of the dips seen in the light output from KIC 8462852.

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I never said that a spheroidal body was the cause of the dips in the output of light.

What I said was that based on 15% of the diameter of KIC which is 313,200 km which is a little over double the diameter of Jupiter which at 139,822 km is approx. 6.69% the diameter of KIC that the object that caused the dim in light of KIC could not have been a swarm of comets.

A swarm of comets measuring in 313,200km in diameter causing a 15% dim really couldn't be possible. An object that massive is size would produce its own gravitational field or fields much the same that a planet would.
 
I never said that a spheroidal body was the cause of the dips in the output of light.

What I said was that based on 15% of the diameter of KIC which is 313,200 km which is a little over double the diameter of Jupiter which at 139,822 km is approx. 6.69% the diameter of KIC that the object that caused the dim in light of KIC could not have been a swarm of comets.
A swarm of comets is not "an object" and need not be particularly massive to occupy a large volume.

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I did the math for the volume of a sphere. A 15% diameter of KIC being 313,200 km in diameter equals 1,376,609.1429 meters.

Haley's Comet 2 is 700 km in diameter. If Haley's Comet 2 is an average sized comet how many Haley Comet 2's would fit into the volume of the 15% dim?

I am using the 15% diameter and sphere as reference to size and how many comets might have been present in the supposed comet swarm.
 
Which is why I mentioned earlier that knowing the opacity of a cometary tail would be useful. Something like that of Saturn's rings perhaps, varying between 0.4 and 1.0. A swarm of comets seems the most likely explanation as Boyajian at al's original paper suggested, unlikely as the scenario was recognized to be.

http://gizmodo.com/that-supposed-alien-megastructure-may-actually-be-a-swa-1744792437

If the objects had been a large comet swarm then as the comet transited around KIC that because of the size of the comet the tail would have shown up in a program like Planet Hunters, of which Tabetha does frequent making comments, the light dip should have shown up as J where the long leg of the J would represent the comet it self with the hook part of J being the cometary tail debris trailing behind the dim that would slowly vaporize over a few days but would still block out some of the light from KIC.
 
I am using the 15% diameter and sphere as reference to size and how many comets might have been present in the supposed comet swarm.
The proposed swarm has an unknown size, shape and density, and knowing how many comets you could pack into a sphere of a specific size won't answer those questions.

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I am using the 15% diameter and sphere as reference to size and how many comets might have been present in the supposed comet swarm.
The proposed swarm has an unknown size, shape and density, and knowing how many comets you could pack into a sphere of a specific size won't answer those questions.

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No the swarm does have a known size because the light caused by the supposed swarm dimmed KIC by 15% and 22% which proves there is a size variable involved that would help support an answer.

If I have a transparent sphere with a hundred marbles in it where the marbles are darker shades of color which cause a dim as the sphere passes across in front of a light bulb that then casts a shadow on a wall I am certain that estimating the diameter of the shadow would help to understand how many possible smaller spheres would comprise the sphere as a total.

The volume of a sphere measuring 313,200 km in diameter = 16,086,585,903,409,344.

The volume of Haley's Comet 2 that is 700 meters in diameter = 179,594,380.

When the volume of the 15% dim in light from KIC or 313,200 km is divided by the volume of Haley's Comet 2 there would be a total of 8,957,176 comets based on the volume of Haley's Comet 2 that would fit inside the volume of the 15% dim in light of KIC.

Although just an example of volume as you can see that in order for a swarm of comets an average size to cause a 15% dim in KIC there would have to be a lot of them.

With the 22% dim in light from KIC possibly resulting from the comet swarm breaking apart there should have thousands of recorded dims.
 
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Please, enough with the spheres, already. It's cross sections and opacity that matter.

Also, if you're going to use numbers, please learn how to use scientific notation and the correct units. For example, the volume of a sphere of diameter 313,200 km is 1.609 x 10^16 km^3 to 3 decimal places. The volume of a sphere of diameter 700 m is 1.796 x 10^8 m^3 to 3 decimal places. Note the different units: cubic kilometers and cubic meters. The second example in units of km^3 would be 1.796 x 10^-1 km^3 to three decimal places. This is why units are important - otherwise you might not be comparing like with like (and you weren't).
 
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Please, enough with the spheres, already. It's cross sections and opacity that matter.

Also, if you're going to use numbers, please learn how to use scientific notation and the correct units. For example, the volume of a sphere of diameter 313,200 km is 1.609 x 10^16 km^3 to 3 decimal places. The volume of a sphere of diameter 700 m is 1.796 x 10^8 m^3 to 3 decimal places. Note the different units: cubic kilometers and cubic meters. The second example in units of km^3 would be 1.796 x 10^-1 km^3 to three decimal places. This is why units are important - otherwise you might not be comparing like with like (and you weren't).
Volume is solved using the radius.


Nope. There is no discussion involving cross sections and opacity. Not until a general volume has been determined to satisfy the possible number of comets.

What is the total area of the sphere? Scientific notation like you said is not an answer its just a notation of a formula.

Actually to find the volume of a sphere the formula is V = 4/3 (.75) x Pi (3.14) x r^3

The volume of the 15% dim in KIC is V = 1.43x10^15 = 1,431,281,810,739,357.2 cubic km.

I'm not certain why two different websites gave me two different answers for the volume of the 15% dim.

Converted to cubic meters = 1.431281811e+24

The volume of Haley's Comet 2 = 179,594,380 m^3
 
So if a planar disk with thickness t and a sphere of equal opacity (1.0, i.e. completely opaque) and radius r were to occult a star of radius R at a distance d from the star very much greater than the distance from earth, the disk being at right angles to a line drawn between the earth and the star, you wouldn't calculate the percentage dimming as being equal to (r/R)^2 x 100% in both cases? You'd use the volumes instead? That's just incorrect. Consider holding up your thumb to the full moon and how a piece of thick card of similar shape to your thumb would have exactly the same effect on blocking the light.
 
So if a planar disk with thickness t and a sphere of equal opacity (1.0, i.e. completely opaque) and radius r were to occult a star of radius R at a distance d from the star very much greater than the distance from earth, the disk being at right angles to a line drawn between the earth and the star, you wouldn't calculate the percentage dimming as being equal to (r/R)^2 x 100% in both cases? You'd use the volumes instead? That's just incorrect. Consider holding up your thumb to the full moon and how a piece of thick card of similar shape to your thumb would have exactly the same effect on blocking the light.

That's relative to a distance between the viewer the object being held and the Sun.

If I able to leave that card in the same place where it blocked out the sun and moved away from the location the card would get smaller and smaller. So in reality the card has not blocked the light at all because light is still seen around the card. If we were to place the card right up against the sun the sun would loom large over the card like the card did the sun.
 
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You should go proselytize some place else.

http://www.universetoday.com/122865...62852-shattered-comet-or-alien-megastructure/

Volunteers with the Planet Hunters project, one of many citizen science programs under the umbrella of Zooniverse, harness the power of the human eye to examine Kepler light curves (a graph of a star’s changing light intensity over time), looking for repeating patterns that might indicate orbiting planets. They were the first to meet up with the perplexing KIC 8462852.



This magnitude +11.7 star in Cygnus, hotter and half again as big as the Sun, 1showed dips all over the place.2 Around Day 800 during Kepler’s run, it faded by 15% 3 then resumed a steady brightness until Days 1510-1570, when it underwent a whole series of dips including one that dimmed the star by 22%. That’s huge! Consider that an exo-Earth blocks only a fraction of a percent of a star’s light; even a Jupiter-sized world, the norm among extrasolar planets, soaks up about a percent.


1. Looks like a possible small cluster of asteroids without the dust that because the orbiting asteroid belt is far away from KIC the dust might not absorb as much light. 2. then a large object possibly a planet at day 800. then nothing for 710 days when the 22% dim and other dims take place.

Like I stated and even the article states Jupiter causes only a fraction of a percent of a dim.

That would make the comet swarm huge like the article refers to. Much larger than even Jupiter.

If we go back to AZ' roadrunner thrust move card experiment and look at the card as an object and us as Kepler looking at KIC from far away we can see that the objects would have to be closer to Earth than they were to KIC in order to block put that much light. But still a 15% and 22% dim could have resulted in a chance alignment of objects within the Oort cloud blocking out the light.
 
If the dim in light wasn't caused by huge planets or a comet swarm the only other celestial event that could cause a dim of 15% to 22% with smaller dims would have to be a WMAP Cold Spot.

Voids mentioned in the article have been found before but not as large. There could therefore possibly be regions of space where smaller WMAP's / CMB would be located.

If the idea proves true then it would prove that space is the thing that is moving. Because if the WMAP is a region in space that is a void then it wouldn't move and would remain stationary causing the same dim in light from KIC all of the time.

http://www.space.com/4271-huge-hole-universe.html

The CMB would cause photons to lose energy. In this case perhaps the CMB passed between Kepler and KIC and caused the photons to lose energy thus causing the dim in KIC 8462852.
 
So if a planar disk with thickness t and a sphere of equal opacity (1.0, i.e. completely opaque) and radius r were to occult a star of radius R at a distance d from the star very much greater than the distance from earth, the disk being at right angles to a line drawn between the earth and the star, you wouldn't calculate the percentage dimming as being equal to (r/R)^2 x 100% in both cases? You'd use the volumes instead? That's just incorrect. Consider holding up your thumb to the full moon and how a piece of thick card of similar shape to your thumb would have exactly the same effect on blocking the light.
I tried to explain this earlier in the thread. It didn't get through.
 
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