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

The 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 then 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.