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Astronomy Year / Week 02 / Thursday
4/6
Week 02 · The Moon Changes

Thursday

Why the shapes change
// Moon shapes and a moon log
⏱ about 15 min

Thursday: Why the shapes change

Raven holds a ball. Rocket holds a flashlight.

"The Sun always lights half of the Moon," Nova says.

Raven walks the ball in a circle around her head. "What do you notice?"

Nova blinks. "Hint: watch how much of the lit half you can see."

Half lit, always

The Sun always lights half of the Moon.

The Moon travels around Earth.

As it moves, we see more or less of the lit half.

That is why the shapes change.

Try it
Make the room dark.
A grown-up holds a flashlight still on one side.
Hold a ball out in front of you.
Turn slowly in a circle and watch the ball.
Find a crescent, a half and a full shape!
Safety first
A grown-up holds the flashlight.
Clear the floor so you do not trip.
Do not shine the light in anyone's eyes.
Moon ideaTrue or false?
The Sun always lights half of the Moon.?
The Moon travels around Earth.?
Phases happen because the Moon breaks into pieces.?
We see different amounts of the lit half.?
WHY THIS EXERCISEThe phases come from where the Moon is as it travels.
THINK IT THROUGH
  • Read the question.
  • Tap your answer.
At new moon, where does the lit half face?
At full moon, how much of the lit half do we see?

Where is the Moon?

At new moon, the lit half faces away from us.

At first quarter, we see half of the lit half.

At full moon, we see the whole lit half.

Where the Moon is in its trip makes the phase.

MOON MODEL CHECK
  • Read the question.
  • Tap your answer.
In the Try it, what was the ball?
In the Try it, whose head was Earth?
At first quarter, how much of the lit half do we see?
Does the Moon stop being half lit at new moon?
WALK THE MOON AROUND
  • Tap a card.
  • Then tap its spot.
1First
2Next
3Then
4Last
Draw the Moon half lit by the Sun. Shade the dark half.

You explained the Moon phases! Tomorrow we start a moon log.

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