You may be surprised to know that the stars also possess light just like the sun. According to the
scientists, the stars
are made up of hot gases which lighten them up.
If you look at the sky in the night time, you will notice that while some stars shine very brightly, others look very dim at the same time. This is because of the difference in temperatures of the gases of individual stars. The stars with higher
temperature shine brightly compared to the others. This is why the
scientists have named some stars as the Cold Stars or the Dark Stars.
Another observation about the stars is that, some of them emit white light, some yellow and some, even blue light. This is because of the difference in composition of gases of individual stars.
According to the scientists, the sun is also a star. It is a medium sized star as compared to the other stars in the sky, because there are numerous stars, which are smaller than the sun, and still numerous others which are quite bigger than the sun, but due to the tremendous distance from our earth, they seem to be quite smaller in size.
The stars are divided into different groups according to their spectrum. Spectrum can be defined as that amount of light which is emitted by a single star. In the series of spectrum, there are red stars at one extreme, blue at the other, and the sun, called as the yellow star, lies in the middle of this series.
The blue stars are bigger in size and are brighter and hotter that the others. Their temperature can range up to about 27,750 degrees, or even more than that. The red stars are relatively much cooler and less bright as compared to the blue ones. Their temperature ranges up to about 1,650 degrees, or even less than that.
The stars lie too far away from our earth. Proximal is the nearest star to our earth, which lies at a distance of about 4 light years from the earth. The farthest star from our planet, which can be seen without the help of a telescope lies at a distance of about 8,000,000 light years. The scientists use the telescope as a powerful tool to visualize millions of such stars which cannot be seen with the naked eye!