Page 142 - Innovator's Science-8

11 Keeping Time

with the Skies

Intended Learning Outcomes
How Does the Moon's Appearance Change and Why?
Phases of the Moon
Locating the Moon
How did Calendars come into Existence?
Understanding the Phases of the Moon
The Moon's Cycle of Phases
Lunar Calendars
Solar Calendars
Luni-Solar Calendars
The Indian National Calendar
Are Festivals Related to Astronomical Phenomena?
Why do we Launch Artificial Satellites in Space?

Stepping Stones

1. Have you seen the stars in the morning me? If not, why?
2. Have you no ced the Moon in the sky during the day me? What do you think
causes it to be visible even when the Sun is shining?
3. How did our ancestors measure me and calculate the planets in ancient
Science mes?
Bytes

The Moon can be seen during the day because it shines by reflecting
Testimony
Although the Moon's sunlight, and depending on its position in the sky, it can be visible both
surface looks bright it is during daylight and at night. The reason it doesn't always look like a full
actually made of dark
volcanic rock. The fine circle is due to its phases. As the Moon orbits Earth, we see different parts
dust on its surface of the sunlit side. Sometimes we see the whole lit side—a full moon—and
reflects sunlight strongly, other times only a portion, such as a crescent or half-moon. This change
which makes the Moon
appear much brighter happens over a regular cycle of about a month. It's not because of a lunar
than it truly is. eclipse; eclipses occur only when Earth's shadow falls on the Moon, which

is rare. The everyday changing shape is simply due to how sunlight hits the
Moon and how much of that lit part we can see from Earth.

HOW DOES THE MOON'S APPEARANCE CHANGE AND WHY?
If we keep observing the Moon every day for a month, we will notice that its

shape does not remain the same. The bright portion of the Moon that we

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Science-8