The universe is a vast ocean of empty space. The word “Universe” comes from the Latin word “Universum” meaning “the whole” or “everything together”. It includes all space i.e. stars, planets, satellites, galaxies, nebulas and comets.

Scientists believe that the universe began about 15 billion years ago. According to ‘BIG BANG’ theory, all energy and matter, which were concentrated into a small volume exploded and has been expanding since then. It is not known how the ball of fire came into existence.

Early universe had no clear shape or structure. As the universe kept spreading out, the mass of gases began to take form. It became what is called a Super galactic Group. This group than began to break and form galaxies. The universe has many galaxies. A GALAXY is a huge group of stars, millions of kilometer across and each star is a huge ball of hot glowing gas. Our galaxy is THE MILKY WAY. The Milky Way galaxy contains about 100,000 million of them. The universes contain thousands of millions of galaxies.