Our Universe (Geography) - Cosmology

The study of universe is known as Cosmology.

Cosmology = Cosmos (Universe)+ Logos (Study)
The universe is commonly defined as the totally of everything that exists including all physical matters and energy, the plants, stars, galaxies and contents of intergalactic space.
The universe comprises of billions of galaxies. The galaxies are made up of millions of stars held together by the force of gravity and these stars account for most of the masses of the gravity. Andromeda is our nearest galaxy.
Our own galaxy is called the Milky way (or the Akash Ganga) and it contains about 100 billions stars and one of these is our sun.

Planets and other object go round the sun and make up the solar system with the sun at the centre. Lastest known Galaxy is the Dwarf galaxy.
Evolution of universe is explained by the Big Bang theory. Big Bang was an explosion that occurred 15 billions years ago, leading to the formation of galaxies of stars and other heavenly bodies.