Stars and the Solar System NCERT Science Class 8 Chapter 17 Summary Note

Stars and Solar System


Celestial objects
The stars, the planets, the moons and many other objects in the sky are called celestial objects. 

Full Moon Day 
The day on which the whole disc of the moon is visible is known as full moon day. 

New Moon Day
On the fifteenth day after full moon day, the moon is not visible. This day is known as new moon day. 

Crescent Moon 
The moon whose only a small portion appears in the sky, is called crescent moon. 

Phases of Moon 
The various shapes of the bright part of the moon as seen during a month are called phases of moon. 

The moon doesn't produce its own light. 

We see the moon because, the sunlight falling on it gets reflected towards us. 

The moon rotates on its axis. 
The moon revolve around the Earth. 

The moon has no atmosphere, no water, 

Star
The sun is also a star. 
Sun appears larger than other stars. Because-
-Stars are millions of times farther away than the sun. 
Stars are not visible during day time. Because
of the bright sunlight. 
Stars appear to move from east to West. Reason- Earth rotates from West to East. 
Pole star situated in the direction of the earth's axis. So it doesn't appear to move. 



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