It is said that clouds of gas and dust condensed to form solar system about 4.6 billion years ago. This process of condensation leads to formation of a disc. The mass of this disc is very larger than its celestial portion, heats up to form a new star. If disc forms several small bodies then it leads to the formation of a planetary system. If the planets are situated closer to the star around which they orbit, then they lose their gaseous envelope due to intense heat of the star and small rocky planets are formed. Where as planets which are so far away from the star become large gaseous bodies.
The solar system consists of Sun and other members of the family consisting of several celestial bodies, which revolve around it. The Sun is at the center of this system and has light of its own. There are nine major planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.
Uranus, Neptune and Pluto are gaseous planets as they are far away from us, they don’t affect us, there fore we will take only 9 planets, and they are Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn, Rahu and Ketu.
Rahu / Ketu are not celestial body they are shadow planets.
Please click on the following planets to know more about it: