First  - Astronomers believe the universe began in a Big Bang (expansion) about 14 billion years ago. At that time, the entire universe was inside a bubble that was much smaller than a pinhead called a singularity. It was extremely hot and dense., Second - Then it suddenly expanded. The universe that we know was born. Time, space and matter all began with the Big Bang., Third - In a fraction of a second, the universe grew from the size of a single atom to bigger than the size of a galaxy. It kept on growing at a huge rate and is still expanding today., Fourth - Within the first few seconds, protons, neutrons and electrons were made. However, it was too hot for these to combine to form atoms., Fifth - After 300, 000 years, the temperature had dropped enough to allow atoms of smaller elements, for example, hydrogen and helium, to form., Sixth - After a billion years these giant clouds of atoms were pulled together by gravity to make the first stars and galaxies., Seventh - After 5 billion years these 1st stars died, exploded and forced new heavier elements into space. These formed new stars, planets, planetary systems and galaxies, including our own solar system., Eighth - Evidence for the big bang expansion is shown by the presence of Cosmic Background Radiation left over from the Big Bang and the red shift in light showing that objects in the universe are continuing to move away from each other.,

Big Bang Expansion

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