When the stars blinks, what actually they does?

Question

I often saw some stars blinking with multiple colours(red, blue, white) respectively. Ive heard about red shift, but what about the other colours? Did they have 'shift's too?

Answer 1

Blinking/flickering stars are due to our atmosphere. But more importantly, due to heat rising from the earth's surface.

If you were in space, the stars would be constant, since the medium is practically a vacuum and the light rays are not refracted. However, once you enter our atmosphere, the air medium will cause the white light from the stars to be refracted into different colors.

However, when heat rises from the earth, esp at night, the air will have varying refractive indices. Hence, the light from the stars will be refracted more at different times, causing the flickering.

Another example if this is if you are looking at a bright light in the distance, close to the horizon on a hot day. Most definitely you would see the heat rising from the earth, and the light would be slightly flickering also. In addition, if you are atop a hill at night, looking down at a city or town, its lights would also be flickering. It is the same principle here that applies to the blinking stars.

I hope this helps.

Answer 2

The different colours arise due to the refraction and scattering of light as it passes through the atmosphere and interstellar space. Yes other shifts are possible. The red shift is actually an effect of stars moving away from us. If any star had a blue or violet shift, it would be moving towards us.

Answer 3

I believe sebastian is mostly correct. If it were solely the atmosphere then planets would also blink. The bursting of stars is one thing. You must also remember that there is a lot of distance between us and a star which gives a lot fo room for objects to intervene in that small subtended angle to our eye.

The atmosphere causes some wavering in all light but that is not the reason that stars seem to appear to blink. The blinking does not exist for planets. Venus is a good example because it is the morning star (usually seen from the US just above the horizon just before dawn near where the sun would come up. )

Answer 4

The blinking of star is caused by the distortion of the light by the not perfectly clear atmosphere. Due to the fact any transparent object with a refraction index other than the 1 of perfect vacuum will bend the light differently as a function of its frequency -- just like a prism does -- the perturbation of the atmosphere will create a rainbow effect.
This is unrelated to the redshift/blueshift effect which affects all colors equally all the time as a function of speed, red and blue are only used as a mean to tell which direction all the colors are affected, either towards the lower frequency (red) or higher frequency (blue).

Answer 5

Stars 'Twinkle' due to the layers of atmosphere between the star are us. Imagine looking at something in the bottom of a pool. it seems to waver around, but we know it isn't actually moving at all.

Stars are actually all different colours, depending on what fuel they are burning, their size, and the heat output. Most stars are red, blue, white or yellow. Our star is yellow, some can look green, orange, etc.

Doppler shift is usually red, if something (normally relating to another galaxy) is moving away, or blue if it is moving towards us, but it is a form of radiation strength, imperceptable to the human eye.

If it the star seems to flash red, blue and/or white, wait a few minutes and see if it moves, it may be a plane.

Answer 6

Yes, but that's not why they flicker like that. The flicker is due to filtering of its light through our atmosphere...you'll tend to notice it when a star is closer to the horizon where the air is thicker than it is overhead.
Red shifts and blue shifts are related to the Doppler effect...red shifted if an object is moving away....blue shifted if its moving towards you. That can only be detected by spectrometers, the naked eye can't pick that upo

Answer 7

The blinking effect is because of 2 reasons : one is due to the chromatic aberation that our atmosphere produces to the human eye and all optical equipment and second is due to the bursting process of light that every star undergoes. Every star is a sun, with its proper light. No blinking? Must be a planet. See, Venus.

Answer 8

the blinking results from effects caused by the atmosphere, slightly modifying the light.

'having a redshift' means the star is more or less fast moving away from your position the more redshift, the faster the motion.
the underlying principle is called doppler-shift, which you may know from cars passing by, having a higher or lower sound when they pass. the sound (in case of the stars, the light) is compressed if it comes towards you. or relaxed if its moving away from you.
redshift / blueshift cause these colors represent both ends of the spectrum of visible light.

Answer 9

I have heard that the stars blink because our atmosphere comes between us and the stars. You should go over to www.spaceweather.com and ask them over there its the NASA sight and they got really cool information.