Understanding twinkling of stars in the night sky
In a clear dark night we all are fascinated by the stars in the sky. Those who have interest in Astronomy might be knowing the shapes of the constellations that stars form and their appearance and apparent movement in the night sky (of course due to rotation of earth around its axis).One phenomenon that is very prominent is the twinkling of the stars. We see them as specs having different brightness but they all twinkle as if they are shivering in cold deep out there.
The reason for this twinkling of stars is the atmosphere of the Earth. When the light coming from a star enters the atmosphere of Earth then it is refracted and the direction of light goes on changing slightly and creating an illusion of twinkling of star. Because of the great distance of the stars we could see this twinkling due to the atmospheric refraction of the light coming from them.
Another interesting thing is that in addition to the stars we also see the planets of our solar system in the night sky which also appear to us slowly moving across these constellations which is actually the deep space background for the planets. As the planets are relatively very near to us in comparison to the stars and they do not have their own light but a part of the sunlight is reflected from them and that is why we see them so in that case there is no twinkling of these planets and we can distinguish them in the night sky simply by this fact that the stars twinkle but planets do not.
Have you ever observed these things with naked eye or using a telescope?
