Thursday, November 15, 2007



It is a star of the Solar system. The other objects including planets, comets, dust particles etc. orbit the sun.
The composition of the Sun is as follows :
Hydrogen - 74% of its mass value
Helium - 25% of its mass value
Oxygen – 0.75% of its mass value, and
Other elements (Carbon, Iron, Nitrogen, Silicon, Magnesium, Sulphur etc. – 0.25% of
its mass value.
The temperature at the Surface is approximately 5500 Degree Celcium which forms white colour but because of scattering in atmosphere, it appears yellow from Earth.
It generates energy by nuclear fusion of hydrogen into helium in the form of light, ultra-violet rays, X-rays, Gamma Rays, Cosmic Rays, Radio Waves etc. It rorates in circular path around galactic center with a speed of 220 Km. per second.
Diameter of the Sun= 1.4x109 m (it is approx. 109 times larger than Earth).
Surface Area = 6x1018 sq. metre
Volume = 1.4x1027 cubic metre.
Mass = 1.99x1030 Kg. (approx. 3,33,000 times of Earth).

Solar System
There are 8 planets as follows :

1. Mercury No Moon
Distance from the Sun = 57.6 million Km.
Time to orbit the Sun – 88 days.
Temperature at Day time 400oC to –200oC during night.
Having longest day, nearest from sun.
Smallest Planet.

2. Venus No Moon
Distance from the Sun = 107.5 million Km.
Time to orbit the Sun – 225 days.
Hottest Planet of solar system.
Brightest planet.

3. Earth Moon – 1
Only planet where life is possible.
Have tallest mountains and water on Earth.

4. Mars Moon – 2
Distance from the Sun = 225.5 million Km.
Time to orbit the Sun – 687 days.
It seems RED from Earth.

5. Jupiter Moon – 60
Distance from Sun = 773 million Km.
Time to orbit the Sun – approx. 12 years
Biggest Planet of Solar system
Having deepest Oceans, shortest day and strongest magnetic field.

6. Saturn Moon – 31
Distance from sun = 1418 million Km.
Time to orbit the Sun – 29 ½ years

7. Uranus Moon – 27
Distance from the Sun = 2853 million Km.
Time to orbit the Sun – 84 years.

8. Neptune Moon – 13
Distance from the Sun = 4500 million Km.
Time to orbit the Sun – 165 years approx.

PLUTO - Now it is a Dwarf Planet of Sun. Farthest planet from the Sun.


The age of the Earth, according to the Geologists, is approximately 4.6 billion years.
The mass of the earth is approximately 5.98x1024 Kg. The composition of the Earth is as follows :
Iron 32.0%
Oxygen 30.0%
Sulhur 3.0%
Silicon 14.5%
Magnesium 14%
Nickel 1.7%
Calcium 1.5%
Aluminium 0.5%
Other Elements 2.8%

Orbital Speed = 1,00,800 Km./hour i.e. approx. 30 Km. per sec.
Period of Revolution round the sun = 365 Days, 5 Hours, 48 Minutes and 46 Sec.
Time of Rotation (onits own axis) = 23 hours 56 minutes and 4 seconds.

Total Land Area is 29% i.e. 14,90,00,000 Sq. Km.
Total Water/Ocean Area is 71% i.e. 38,30,00,000 Sq. Km.

The area-wise distribution of the Earth is as follows :
Asia 29.5%
Africa 20.0%
North America 16.3%
South America 11.8%
Europe 6.5%
Australia 5.2%
Antartica 9.6%

97% of total earth’s water is salt and hard water. Less than 3% of water is fresh (drinkable) on which 2.25% water is in the form of Iceburgs, 0.6% is stored underground and remaining 0.15% is in lakes and rivers etc.

There are 4 Oceans :
Pacific Ocean 16,60,00,000 Sq. Km.
Atlantic Ocean 8,66,00,000 Sq. Km.
Indian Ocean 7,35,00,000 Sq. Km.
Arctic Ocean 95,00,000 Sq.Km.

Few of major Sea are as follows :
South China East China Caribbean
East Sea Andaman Hudson Bay
Black Sea Red Sea Mediterranean
Arabian Sea Caspian Sea Norwegian Sea

Few major Lakes are :
U.S.A. Superior, Michigan, Ontario, Erie, Great Bear, Huron.
Africa Malawi, Victoria, Tanganyika
Asia Aral Sea, Baikal,
Canada Great Slave, Winnipeg

Sahara Desert in North Africa is the largest one. The other Deserts are Thar (India and Pakistan), Great Sandy and Great Victoria (Australia), Kalahari (South Africa), Arabian (Middle East) and Sonoran, Mohave (S-W USA).`

Nile River in Africa is the longest river in the world which flows approx. 6500 Km. In India Brahmputra river is the longest river. It originates from Tibet and enters into Arunachal Pradesh. Only in India, it covers approx. 2900 Kms.

Mount Everest is the Highest mountain in the World in Nepal – Tibet. K2 is the highest mountain in India. It is 28700 ft. high.


The moon is the only satellite of the Earth which is fifth largest moon in the Solar system. The center to center distance from Earth to moon is approx. 3,84,400 Km. Its diameter is 3474 Km. Its circumference is approx. 10,900 Kms. The mass of the Moon is 7.35x1022 Kg. The Gravitational force is about 1/6th of Earth’s gravitation.
It makes a complete orbital round the earth in 27 days 7 hours 43 minutes and 6 second.
Escape Velocity of the Moon is 2.38 Km/sec.
Surface Temperature of the Moon is 100K in the night to 390K in day time.