Page 144 - Innovator's Science-8

PHASES OF THE MOON

As you continue your observation, you will notice that the Moon's bright
portion keeps changing. After the full Moon, it begins to shrink over the
next few days, turning into a half-circle and later into a thin crescent before
disappearing altogether. This period, when the illuminated part of the

Moon becomes smaller, is known as the waning phase. When the Moon is
not visible at all, it is the new Moon day.

After the new Moon, the bright portion again starts to grow. In about a
week, it becomes a half-Moon, and in another week, it reaches its full
circular form once again. This growing period is called the
waxing phase. Together, these two cycles waxing and

waning - make up one complete lunar month.
In India, the waxing phase is traditionally known as Shukla

Paksha, while the waning phase is called Krishna Paksha.
The cycle of these bright and dark halves has been
observed for thousands of years and forms the basis of
many ancient calendars and festivals. The Moon's phases
repeat regularly, providing us with a natural and beautiful

Waxing and waning of the Moon way to measure time.

LOCATING THE MOON

When you look at the Moon on successive days at the same time, like at
sunrise, you will notice it appears in different parts of the sky. On a full
Moon day, the Moon is nearly opposite the Sun—meaning when the Sun

rises in the East, the Moon is almost setting in the West. As days go by and
the bright part of the Moon gets smaller, it moves closer to where the Sun is
in the sky. When the Moon shows a half-circle shape, it is directly overhead
at sunrise. A few days later, the crescent Moon looks even closer to the Sun

Science in the sky. Knowing whether the Moon is waxing (getting bigger) or waning
Bytes
(getting smaller) helps us find where and when to see it. Usually, a waxing
Moon is easiest to see at sunset, and a waning Moon is best seen at sunrise.
Testimony
The same side of the Because of these movements, the Moon always rises and sets at different
Moon takes exactly the
same me to rotate on its times than the Sun.
axis as it takes to revolve Many people think that the Moon always rises at sunset, but that is not
around the Earth— about
27.3 days. This synchronal true. Its rising time changes by about 50 minutes every day. You can check
mo on is why we never the exact time in a newspaper or on the website of the India Meteorological
see the ‘far side’ of the Department (IMD). Watch this for a few consecutive days-you will notice
Moon from Earth.
that each day the Moon rises a little later than before. Sometimes, the

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