GEOGRAPHY NOTES FOR IAS ,SSC ,PCS AND OTHER GOVT JOBS.

GEOGRAPHY meaning the study of the physical features of 

the earth and its atmosphere, and of human activity as it 

affects and is affected by these, including the distribution of 

populations and resources and political and economic 

activity.


EARTH AND SOLAR SYSTEM.

Some celestial bodies are very big and hot. They

are made up of gases. They have their own heat and

light, which they emit in large amounts. These celestial

bodies are called stars. The sun is a star.

While watching the night sky, you

may notice various patterns formed by

different groups of stars. These are

called constellations. 

Ursa Major or Big Bear is one such constellation. One

of the most easily recognizable constellation is the small bear or

Saptarishi  (Sapta-seven, rishi-sages). It is a group of seven stars  that forms a part of the large Ursa Major Constellation.

CONSTELLATION IMAGE.

3.    The North star indicates the north direction. It is also

called the Pole Star. It always remains in the same position in the sky.

3.    Some celestial bodies do not have their own heat

and light. They are lit by the light of the stars. Such

bodies are called planets. The word ‘planet’ comes from

the Greek word “Planetai” which means ‘wanderers’.

The earth on which we live is a planet. It gets all its

heat and light from the sun, which is our nearest star.

Jupiter , Saturn and Uranus have rings around them .These are belts of small debris.These rings may be seen from the earth

with the help of powerful telescopes.

Humans have always been fascinated gazing at the night sky. Those who study the celestial bodies and their movements are called astronomers. Aryabhatta was a famous astronomer of ancient

India. Today, astronomers All over the world are busy

exploring the universe.

The sun is about 150 million km away from the earth.

Mercury is nearest to the sun. It takes only about 88 days to complete one round along its orbit. Venus is considered as ‘Earth’s-twin’ because its size and shape are very much similar to that of the earth.

In a meeting of the International Astronomical Union, a decision was taken that Pluto like other celestial objects (Ceres, 2003 UB313) discovered in recent past may be called ‘dwarf planets.”

The earth is the third nearest planet to the sun. In size, it is the fifth largest planet. It is slightly flattened at the poles. That is why, its shape is  described as a Geoid. Geoid means an earth-like shape.

The earth appears blue because its two-thirds surface is covered by water. It is, therefore, called a blue planet.

The Moon Our earth has only one satellite, that is, the moon. Its diametre is only one-quarter that of the earth. It appears so big because it is nearer to our planet than other celestial bodies. It is about 3,84,400 km away from us.

The moon moves around the earth in about 27 days. It takes exactly the same time to complete one spin. As a result, only one side of the moon is visible to us on the earth.

Light travels at the speed of about 300,000 km per second. Yet, even with this speed, the light of the sun takes about eight minutes to reach the earth.

Neil Armstrong was the first man to step on the surface of the moon on 29 July 1969.

A Satellite is a celestial body that moves around the planets in the same way as the planets move around the sun.

A Human-made Satellite is an artificial body. It is designed by scientists to gather information about the universe or for communication. It is carried by a rocket and placed in the orbit around the earth. Some of the Indian satellites in space are INSAT, IRS, EDUSAT, etc.

Apart from the stars, planets and satellites, there are numerous tiny bodies which also move around the sun. These bodies are called asteroids. They are found between the orbits of Mars and Jupiter.

The small pieces of rocks which move around the sun are called meteoroids. Sometimes these meteoroids come near the earth and tend to drop upon it. During this process due to friction with the air they get heated up and burn. It causes a flash of light. Sometimes, a meteor without being completely burnt, falls on the earth and creates a hollow.