02 March, 2011

Planets.... The Wanderers in the Sky

Billions of years ago, there was an enormously great and huge swirling cloud of gas and dust. This clout packed together to such an extent that eventually it became extremely hot. With the passing time the center of the cloud formed our Sun. The rest of the cloud helped to form the planets of our solar system.
The eight planets in our solar system revolve around our Sun or their specific paths named as orbits. Beginning with the one closest to the Sun, the names of these planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
Until a few years ago astronomers and scientists considered another heavenly body named Pluto too a planet but in 2006 it was declared as a dwarf planet. This was because firstly Pluto is too small to be considered as a planet and secondly it has a strange composition.
The planets have been divided into two basic groups according to their composition. Firstly there are Earth-like planets and secondly there are Jupiter-like planets. Earth-like planets are close to the Sun and are made up of rock and metal. These planets are Mercury, Venus, Earth, and Mars. The other type of planets are larger and at a greater distance from the Sun. Names of these planets are Jupiter, Saturn, Uranus, and Neptune. These four planets do not have a solid surface, rather they are made up of gases and liquids.
Each planet rotates on its axis along with its circulation around the sun. An axis is like an imaginary pole going through a planet's centre from one end to the other. The planet spins as if a giant hand had given this pole a great twist.
Most planets rotate from west to east. Only Venus and Uranus rotate from east to west. This is why on these planets the Sun seems to rise in the west and set in the east.
Scientists have found three planets orbiting the star Upsilon Andromedae, a star much like our Sun. Some are of the view that it means there could be life on one of the planets.

No comments:

Post a Comment