Question
How do stars form?
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Answer
There are huge clouds of gas and dust in the empty spaces between the stars in a galaxy. These clouds are called interstellar clouds. The size of an interstellar cloud is about a few light years.
When an interstellar cloud starts contracting due to some disturbance, its density and temperature increase. This results in formation of a dense sphere of hot gas and nuclear energy generation starts at the centre of the star. Therefore, the gas sphere becomes self-luminous. Thus a star is formed, i.e., a star is born.
A huge interstellar cloud can produce thousands of stars at a time.
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