Star

A star is a big ball of super hot light in space. The Sun is the star closest to Earth. At night, you can see many other stars in the sky. They look like tiny dots of light because they are very, very far away. People have given names to the brightest stars. There are more stars in space than we can count. Scientists think there are more stars than grains of sand on all beaches. But you can only see about four thousand stars without a telescope.

Stars are born from big clouds of gas floating in space. These clouds are mostly made of two gases called hydrogen and helium. A star's life depends on how big and heavy it is. A star shines by burning hydrogen deep inside itself. This burning creates heat and light that travels out into space. When a star gets very old, it stops shining. Then it becomes something different, like a white dwarf or a black hole.

Stars help create new things in space. When stars burn, they make heavy materials. These materials spread out into space when stars explode. New stars form from these materials. Scientists can learn about stars by watching them carefully. They look at how bright a star is and what colors it makes. They also watch how stars move across the sky.

Stars often travel together in space. Two stars can orbit around each other like dancers. Many stars live together in huge groups called star clusters. These groups hold billions of stars together using gravity. Galaxies are even bigger groups of stars held together by gravity. Our Sun is just one star in a galaxy called the Milky Way.