Look up at the sky on a clear, moonless night and the twinkling points of light you can see scattered across the heavens are stars. To the naked eye about 3,000 stars are visible from Earth. With the aid of instruments, scientists can see about 1,500 million stars!
Stars are formed when the gigantic clouds of gas and dust in space collapse inwards under the pull of their own gravity.When this happens, the pressure at the core becomes so great that the heat releases energy which keeps a star burning brightly for most of its life, 10,000 million years. Our Sun is a typical star. Throughout the vastness of space, stars are gathered in galaxies numbering millions of stars. The universe contains millions of galaxies! We give names to constellations, recognisable clusters of stars, like Orion, the Plough, and Cassiopeia.
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