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SAI INTERNATIONAL SCHOOL
Class 8
Lesson Notes
Subject-Physics
CH- Stars and Solar system
Subtopic- Phases of Moon

 The stars, the planets, the moon and many other objects in the sky are known as
the celestial objects. So, whatever heavenly bodies we see in the sky are known
as celestial objects.
 The study of celestial objects and associated phenomena is called astronomy.
The Moon:
 The surface of the Moon is barren and all covered with dust.
 There are Craters or bowl-shaped cavities present on the surface of the Moon.

 There are steep and high mountains present in huge numbers on the Moon.
 Some of the mountains are as high as the highest mountains found on the earth.
 There is no presence of water and atmosphere on the moon.

 We know that the Moon is a natural satellite of the earth that revolves around the
earth in a fixed orbit.
 Also, the Moon does not emit any light of its own but it reflects the light of the sun
that falls on it.
 Phases of Moon: The various shapes of the bright part of the Moon as seen
during a month are called phases of the moon.
o New Moon day: When Moon is not visible
o Full Moon day: When full Moon is visible

o Reason for phases of moon: As the moon revolves around the earth the
part of the bright part of Moon facing the earth keeps on changing which
results in phases of