why moon is called natural satellite of earth

why moon is called natural satellite of earth

 A satellite is a solid heavenly body that revolves around a planet in the same way as the planet that go round the sun. As a result, the satellite also moves around the sun. A satellite is opaque material that does not have its own light or heat. Satellite like planet shine by reflecting light from the sun. 

There are more then 50 satellite in our solar system. Almost all planet have one or more satellite, but Venus and Mercury have no satellite. Our earth has only one natural satellite called the moon. Satrun has the greatest number of satellite that is 22, Jupiter has 19, Uranus has 21 and Mars has 2. 

Moon - natural satellite:-

The natural satellite of the earth is 'Moon'. It look so large because it is the closest the earth. The moon is the natural satellite of the earth because it's rotate around the earth. It shines because it reflects sunlight. 

The moon take an average of 29.5 days to orbit the earth. At the same time, it also rotates or spin about it's axis once. The time taken for a single rotation and revolution around the earth is the same. Because, we always see the same face of the moon.

There is no atomsphere or water on the moon and the absence of atomsphere makes the day very hot and the night very cold. 

On 21 July 1969, Neli Armstrong, an American astronauts, become the first man to walk on the moon. 

Phases of the moon:-

New moon:- In this condition, the moon's facing unilluminated side to the Earth. The moon is not visible. This situation is called Amavasya.

Waxing crescent:- The moon appears to be partly but less than one half illuminated by directly sunlight. The fraction of the moon's disk that is illuminated keep increasing. 

First quarter:- One half of the moon appears to be illuminated by directly sunlight.  The fraction of the moon's disk that is illuminated keeps increasing.

Waxing gibbous:- The moon appears to be more than one half but not fully illuminated by direct sunlight. The fraction of the moon's disk that is illuminated keeps increasing. 

Full moon:- The moon in which illuminated side faces the earth. The moon appears to be completely illuminated by direct sunlight. This is called full moon or purnima. 

Waning gibbous:- The moon appears more than one half but not full illuminated by directly sunlight. The fraction of the Moon's disk that is illuminated keeps decreasing. 

Last quarter:- one half part of the moon appears to be illuminated by direct sunlight. The fraction of the moon's disk that is illuminated keeps decreasing. 

Waning crescent:- The moon seem partly but less than one half  it would be illuminated  directly sunlight. The fraction of the moon's disk that is illuminated keeps decreasing. 

New moon:- phases cycle starts all over again.