Question Does emitted-light have different properties from reflected light?

Jan 25, 2020
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Does emitted-light have different properties from reflected light, and it is for this reason that we see the stars twinkle in the night sky while the planets do not? Note: I know the explanation that attributes the phenomenon to their variation in distance from Earth.
 
Aug 31, 2020
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This is a very important question and has deep implications. If you would like to read about a new theory of the reflection of light, you might like to read this thread. The question of why stars twinkle is as you suggest, due to the huge distances that the light travels and the refraction that light undergoes.
 
Jan 25, 2020
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This is a very important question and has deep implications. If you would like to read about a new theory of the reflection of light, you might like to read this thread. The question of why stars twinkle is as you suggest, due to the huge distances that the light travels and the refraction that light undergoes.
I think that the stars' light does not appear to twinkle for an onlooker from outer space: their twinkling is correlative with Earth's atmosphere, and, thus, the huge distance their light travels is not, in my opinion, a considered factor. I mean that the refraction the stars' light undergoes occures in the layers of our planets atmosphere, and, as this this refraction does not occure with light refracted by the planets and the Moon as well, it should indicate that there is diference in properties between refleted laight and emitted light. One of these diferences may be that refleted light travels in straight lines, not as a wave.
 
Aug 31, 2020
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The fact is the nearest star to earth is Alpha Centsuri which is approx 40 x 10^12 km distant while the moon is only 2.5 x 10^5 km distant, similarly the sun is 150 x 10^ 6 km distant. There is no comparison between these distances. Yes the earth's atmosphere might be the major cause for the twinkling of stars. But light, of a certain frequency, energy and wavelength is the same whether emitted or reflected.
 
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Jan 25, 2020
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A star 4 light-years from Earth, like Alpha Centauri, should twinkle in a different way from the farthest star visible to the naked eye, if it is a matter of distance.
 
Aug 31, 2020
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It all seems to come down to the earth's atmosphere. Astronauts on the space station see stars shining steadily. Stars seen from the space station do not twinkle.
 
Jan 25, 2020
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You wrote: "But light, of a certain frequency, energy and wavelength is the same whether emitted or reflected." I ask: is this proved mathematically or experimentally?
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Aug 31, 2020
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Light that is reflected is polarized light. That's the difference.
Partially polarised would be more accurate. This is in some part due to the nature of the material it is reflecting off having birefringent properties than anything else. Birefringence is when light falling on the material is dispersed or split into its individual colours. The degree of polarization depends on the angle of incidence and the index of refraction of the reflecting material.

The OP asks whether reflected light; light reflected from the moon and the planets is different from light from stars that is emitted and if this is the reason that stars twinkle. Obviously if reflection is the topic it is a longer discussion. For instance, if light reflects of metal surfaces it does not undergo polarisation and so on.
 
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Feb 19, 2020
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If the question is addressed to me, I have no expertise on that. But it would seem logical that polarized light in would be polarized out.
 

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