Story of stars

 Stars are heavenly bodies,which shine like our sun. They are giant balls of gas made of hydrogen ,bound together by their own force of gravity. They do not have live forever and 'die 'at some point. While very heavy stars expand and explode. Their remains become either a neutron star or a'black hole '.                                                              Did you know that?                                               The twinkling of stars is caused by the swirling air in the atmosphere and does not come from the star itself.                                       A new Star is born every twenty days.            Red star is the coolest  star and blue star is the hottest. Yellow star like the sun have an average temperature.                                             Many stars are thousand times bigger than our sun.                                                                       Very large stars, about twenty times heavier than our sun, expand to become a giant and finally explode. This is known as 'supernova'.