Geography : An Introduction Part 2

Twin Planets :- ​

• Jupiter is the largest planet, then comes Saturn, Uranus, Neptune, Earth, Venus, Mars, and Mercury respectively. Earth and Venus are almost same shape , so they called are twin Planets.

Stars -

• Stars are formed from the cloud and dust particles existing in the galsxy. Mainly they have hydrogen and helium. The life span of stars passes the following stages :-
• Proto stars is formed due to pressure and accumulation of gases and dust particles resultant from the gravity.
• Heat is generated dur to pressure, which results in the proocess of Nuclear fission and hydrogen gets converted into the helium. A large amount of heat and light is produced.

The Sun :- 

• The sun is a star , whose mass is 33300 times more than the mass of the Earth. The average density of the sun is 1.4 and it's period of rotation  is 30 days. The sun is about 15 crore km away from the Earth and the time taken by the light of the Sun to reach of the Earth's 8 min and 16.6 sec.

​​Comets :- 

• Comets are the celestial Object formed from the dust particles gaes etc. Which orbit around the sun. Their tail always remains far from the sun. Temple 1, Helbop, Forbs, Haley, etc are some significant comets. Comets of Haley appear at every 76 years.

​Asteroid :-

• They are thr small stars who rotates around the Sun, between the Mars and the Jupiter. IV Vesta is only asteroid which can be seen.

Geoid :-

• The shape of the Earth is Geoid. Its equpotential perimeter is 40,075 km. And it rotates around the sun in 365 days, 5 hrs , 48 minutes and 48 sec with the speed of the 107160 km / hours.