What makes stars sunshine?

A star is a ball of very hot gas which shines by its own light. Planets, as you know, and our moon too, shine by light reflected by the sun. And planets shine with a steady light while stars appear to twinkle. This is caused by substances in the air between the star and the earth. The unsteady air bends the light from the star, and then it seems to twinkle.

Why does our sun shine? BECAUSE IT IS A STAR ! And not a very big or bright star at that. Compered to all the other stars in the sky, it might be consider medium-sized and medium-bright. There are millions of stars that are smaller than our sun. Many stars are several hundred times larger than the sun. They all look small because they are so far away.

Ever since the days of the Greek astronomers, some 2,000 years ago, the stars g\have been divided into classes according to their "magnitude", or brightness. Another way of grouping stars is according to their spectra, or the kind of light that comes from the stars. By studying the differences in the spectra, the astronomer may learn about the colours, the temperature, and even the chemical composition of the stars.