The Solar System
The Sun, eight Planets, Satellites and other bodies like Asteroids, Meteoroids etc form the solar system. Sun is the head of solar family. All bodies like planets, satellite etc moves around the sun in a fixed path called orbit.
This is the center of solar system made up of hot gases.
In order of distance from Sun, the planets are :Mercury, Venus Earth ,Mars, Jupiter, Saturn, Uranus and Neptune
Mercury is nearest planet to sun where as Neptune is furthest. Venus is called morning and evening star, Mars is known as Red planet. Saturn and Neptune have rings.
The small pieces of rocks which move around the sun are called Meteoroids. When meteoroids come near the earth and fall upon it, due to friction with air they burn.
The Earth is known as Blue planet due to have 2/3rds surface covered with water. Earth has only one satellite known as Moon.
It is about 3,84,400 km away from us. Moon moves around earth in about 27 days.
GLOBE : LATITUDES AND LONGITUDES
Globe is a model of the Earth. A needle is fixed through it in a tilted position, which are called axis. Globe tilted 23.5 degree as earth tilted. Globe have imaginary lines on it called Longitude, latitude, equator, tropic of Capricorn, tropic of cancer.
An imaginary horizontal line drawn on the globe divide it into two parts.
Tropic of cancer:
it is at 23.5 degree in northern hemisphere
Tropic of Capricorn:
it is at 23.5 degree in southern hemisphere.
Longitude are shown by vertical line on globe, is the angular distance, in degrees, minutes, and seconds, of a point east or west of the Prime meridian.
Latitude are shown by horizontal line on globe, is the angular distance, in degrees, minutes, and seconds of a point north or south of the Equator. Lines of latitude are often referred to as parallels.
Motion of earth
Earth has two type of motion called:-
- Rotation ( movement on its axis)
- Revolution(movement around the sun).
Earth takes about 24 hrs. to complete one rotation, this cause day and night where as it takes 365 days and 6 hours to complete one revolution, this causes change in seasons.