Merged Tabby's Star / One Scary Star

steenkh said:
A black hole at the physical size of a proton will only have the gravitational influence of a proton, which is very little, and it will not inconvenience the host star at all. Besides, the Hawking radiation should make it disappear eventually. (I assume you mean mass of a proton; an event horizon of the actual physical size of a proton will still not have a lot of mass compared to the star, but I cannot say how much).
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A black hole the size of a proton would have mass about 0.1-1 billion tons. If it formed during Big Bang, it would have evaporated long time ago.
 
crescent said:
No, it would show up on infra-red. Whatever is blocking the light from this star is, it does not show up on infra-red. It intercepts light from the star, but does not absorb the light and re-emit is as heat.
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When I asked about possible effects of a planet falling into a star I was more thinking of the matter of the planet getting into the star and affecting it in some way, how energy is transferred from the core to the surface or the fusion process in the core if a planetary mass of heavier elements made it's way down there.
 
steenkh said:
A black hole at the physical size of a proton will only have the gravitational influence of a proton, which is very little, and it will not inconvenience the host star at all. Besides, the Hawking radiation should make it disappear eventually. (I assume you mean mass of a proton; an event horizon of the actual physical size of a proton will still not have a lot of mass compared to the star, but I cannot say how much).
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Mark6 said:
A black hole the size of a proton would have mass about 0.1-1 billion tons. If it formed during Big Bang, it would have evaporated long time ago.
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I am talking about the current diameter of the black hole not the mass. That is one formed during the big bang. The exact size is not important. Any mass much smaller than a star (maybe the mass of a small planet?) is what I am talking about. If I am right the star will continue to decrease in brightness. But then at the end it would emit heaps of x-rays, just like a normal black hole eating mass. A big difference is that the amount of radiation would be a lot less and only for a short time. Not sure about the wavelengths. We might only have to wait a few years or a decade or two then the evidence will come in to say I am wrong (with a very small chance of me being right).


Evidence that I am wrong - If I was right then people who know about the subject would have already suggested this idea.
 
shemp said:
It's just Schroedinger's cat playing with the dimmer switch.
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Actually the star doesn't know yet if it's alive or dead, or even if it's a star, so we're observing something that's stuck between star and all other possible objects. Now that we're observing it, the wave function will collapse, but we won't notice for another 1480 years.

(Yes, I know that's not how it works. It's a joke.)
 
Curiouser and curiouser!

http://www.space.com/34303-alien-megastructure-star-strange-dimming-mystery.html

The more scientists learn about "Tabby's Star," the more mysterious the bizarre object gets.

Newly analyzed observations by NASA's planet-hunting Kepler space telescope show that the star KIC 8462852 — whose occasional, dramatic dips in brightness still have astronomers scratching their heads — has also dimmed overall during the last few years.

"The steady brightness change in KIC 8462852 is pretty astounding," study lead authorBen Montet, of the California Institute of Technology in Pasadena, said in a statement. [13 Ways to Hunt Intelligent Alien Life]

"Our highly accurate measurements over four years demonstrate that the star really is getting fainter with time," Montet added. "It is unprecedented for this type of star to slowly fade for years, and we don't see anything else like it in the Kepler data."
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It is uniform across visible spectrum. Tabby's Star has been observed in radio, but not long enough to detect such changes.
 
Mark6 said:
It is uniform across visible spectrum. Tabby's Star has been observed in radio, but not long enough to detect such changes.
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Is there an expected brightness in radio given the star's type and brightness in visible wavelengths? Could that comparison be made?
 
Roboramma said:
Is there an expected brightness in radio given the star's type and brightness in visible wavelengths? Could that comparison be made?
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The spectrum of a black body will depend on its temperature, but the short answer is yes. According to Wikipedia its temperature is known to within +/-120 K. Is the brightness changing because the temperature is changing?

This latest finding seems a lot like the previous finding to me though.
 
Fudbucker said:
But it would be possible to convert the excess heat energy to something like microwaves, right? I mean, if one posits mega-structures (not necessarily a full-on Dyson sphere) as being responsible for the dimming, an objection about excess heat not being detected could be overcome by conjecture that the heat is being converted to other forms of energy.

If the author of the article was willing to mention mega-structures, why wasn't a caveat about converting heat energy included in the article? Should it have been included, or is such speculation totally absurd?
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Any form of energy other than 'heat' would have a large free energy. The free energy, also called the Gibbs energy, refers to the usable part of energy. This means the fraction of energy that is not associated with entropy.

Any other form of energy other than heat energy would be inefficient. In order to use the energy from the sun, entropy has to be created. If the energy were transformed into neutrinos, for instance, the neutrinos would carry the free energy away. Most of the suns energy would go into making neutrinos. The neutrinos would have high kinetic energy, but couldn't be reabsorbed by the civilization. So all that energy would be wasted.

There are few molecules in interstellar space, so heat couldn't be emitted as molecular motion. So the energy would have to be emitted as electromagnetic radiation radiation with a black body spectrum and an energy density consistent with the laws of black body radiation. This EM radiation could be heat.

The maximum efficiency would come about if the temperature of the black body radiation matched the background temperature of the universe. So in principle, the blackbody radiation would come of at 2.9 K, the temperature of the microwave background. It would appear as an sudden increase in microwave radiation, not infrared. So maybe we should be looking for hot spots in the cosmic microwave background (CMB).

The efficiency of the process would be slightly better emitting CMB than infrared blackbody (IRB). However the improvement would not be big. The reason is that the density of the IR radiation on the surface of this object would be very high.

The thermodynamic efficiency would not be determined solely the spectral temperature. Yes, the bigger the peak wavelength the more efficient the process. The efficiency would be determined also by the density of radiation. A 'small' Dyson sphere would have a higher density of radiation then a 'large Dyson sphere'. The amount of free energy would increase with energy density regardless of the peak energy.


Maybe the civilization could convert the energy in microwave radiation with a black body spectrum. However, they wouldn't get the maximum efficiency anyway unless they dispersed it over a wide area much greater than the area over which the civilization lives. This would be thermodynamically efficient. However, it would have a great commuter time.

So I think it is fair to consider the possibility that the sudden dimming was accompanied by an emission of microwave radiation rather than IR radiation.

Still, maybe some of the inhomogeneities in the CMB are not caused by quantum fluctuations. Cosmologists usually explain the inhomogeneities in CMB radiation with inflation theory. However, there are a lot of such inhomogeneities. Maybe a small fraction of CMB hot spots are Dyson spheres! :D
 
alexi_drago said:
Would there be any effect on a star from a planet falling into it?
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You aren't the only one to ponder this question.

Secular dimming of KIC 8462852 following its consumption of a planet

Mark6 said:
Very spectacular effects, but dimming is not among them
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Eating a planet could cause dimming. Read the article. The star would brighten during the impact of the planet with the star, but ejected debris (including moons) still in orbit around the star could produce dimming.
 
Ziggurat said:
You aren't the only one to ponder this question.

Secular dimming of KIC 8462852 following its consumption of a planet



Eating a planet could cause dimming. Read the article. The star would brighten during the impact of the planet with the star, but ejected debris (including moons) still in orbit around the star could produce dimming.
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Good find. Never thought about the impact of a planet on a star, but it could happen and it would make sense. Also the planet could be hard to detect before impact especially if the planet's orbit was not directly between us and the star (which is highly probable).
 
rjh01 said:
Good find. Never thought about the impact of a planet on a star, but it could happen and it would make sense. Also the planet could be hard to detect before impact especially if the planet's orbit was not directly between us and the star (which is highly probable).
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They also model the age of the planetary impact as being up to 10,000 years ago (depending on the mass, and not including light propagation time), so we likely wouldn't have seen it in any case.
 
Ziggurat said:
They also model the age of the planetary impact as being up to 10,000 years ago (depending on the mass, and not including light propagation time), so we likely wouldn't have seen it in any case.
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Agreed, but we would not detect a planet on another star before it is absorbed. It would be almost impossible to prove why a star is fluctuating in brightness. All we can say is that this matches theory.
 
I am going with hydrinos as the explanation. Not when they are formed and emit heat and light, but when they turn back into regular hydrogen. :boxedin:
 
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The original thread is here http://www.internationalskeptics.com/forums/showthread.php?t=308058

I just had a thought. I wonder if it possible that two large planets that are very close to each other are orbiting each other around the star? They would be so close that the smaller one is taking the atmosphere from the larger one and sending it into space. The dipping is what we see when the light from the star goes through the atmosphere. If I am correct the dip in the light would be concentrated at certain frequencies which would tell us what gasses there are in the atmosphere. The larger one could be a gas giant with a weak surface gravity (for its mass) and the smaller one a rocky planet, probably with an iron core. The last sentence could well be wrong though.
 
I suspect that such a theory will get significant substantiation or refutation due to this opportunity to view a nearly full dimming cycle with spectroscopic instrumentation. The leading candidate (consumption of a planet) may likely increase its lead (becoming a fact in many peoples' minds) or get thrown out with this opportunity.

rjh01 said:
The original thread is here http://www.internationalskeptics.com/forums/showthread.php?t=308058

I just had a thought. I wonder if it possible that two large planets that are very close to each other are orbiting each other around the star? They would be so close that the smaller one is taking the atmosphere from the larger one and sending it into space. The dipping is what we see when the light from the star goes through the atmosphere. If I am correct the dip in the light would be concentrated at certain frequencies which would tell us what gasses there are in the atmosphere. The larger one could be a gas giant with a weak surface gravity (for its mass) and the smaller one a rocky planet, probably with an iron core. The last sentence could well be wrong though.
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One Scary Star

So, a friend of mine an I were discussing planetary systems, new and interesting astrological findings when he said, "if ever we see a star, just plop out of existence, we should be scared that another civilization has mastered solar collection."

A couple of years later, I stumbled across this Ted Talk- https://www.youtube.com/watch?v=gypAjPp6eps

This star's output indicates something VERY strange is happening there...
 
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