THE MAKING OF UNIVERSE

How did the Universe begin?
Around 15 billion years ago, all the matter from which our Universe is made was packed into a superhot, superdance fireball less than 1 cm (1/2in) wide. This fireball flew apart in a violent explosion known as the 'Bing Bang', and within a millionth of a second, it had grown to some 16 billion km (10 billion miles) across. It continued to expand, but as it did so it cooled - just as steam rising from a kettle cools as it expands.
Atoms, the building blocks of our Universe, began to form. Over the course of the next few billion years, the force of gravity drew matter together into clumps to form galaxies and stars.

If you look into the sky, what you see is the Universe or at least part of it. The groups of stars known as galaxies, the planet and their moons, the floating lumps of rock, called asteroids, even the cold empty space between them, were formed as many as 15 billion years ago in a sudden flash known as the 'Big Bang'.

The story of the Universe is a remarkable one. It all began 15 billion years ago with a flash and a bang, called the 'Big Bang'. A fireball blew apart, cooled and then clumped together as galaxies and stars, including eventually our own, the Sun.