The Cosmic Landscape Lesson 3: Prehistoric Astronomy, Part 2 1

Motivation Moon’s appearance Moon’s changing

phases Studying the Moon—

a link to our past

The Cosmic Landscape Lesson 3: Prehistoric Astronomy, Part 2 2

Lesson overview What can we observe about the Moon

today that prehistoric people also would have seen?

How can we explain the Moon’s changing appearance?

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Introduction The Moon’s changing appearance—obvious

to any observer How to explain—relative positions of the Sun,

Earth, and Moon

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How can we explainthe Moon’s phases?

Appearance changes over about one month.

“Month” comes from the word “moon.”

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How can we explainthe Moon’s phases? (cont’d)

What the Moon looks like at night “Rising” in the east and “setting” in the west When the Moon rises and sets How the Moon looks at different times

What causes the Moon’s changing appearance

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How can we explainthe Moon’s phases? (cont’d)

(A) The cycle of the Moon’s phases from new to full and back again. (B) The Moon's phases—pictures in the dark squares show how the Moon looks to us on Earth.

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How can we explainthe Moon’s phases? (cont’d)

How the Sun lights the Moon’s surface

When you can see a full Moon (position 5)

The Cosmic Landscape Lesson 3: Prehistoric Astronomy, Part 2 8

Lesson review

Where the Moon “rises” and “sets” When the Moon rises and sets How the Moon looks at different times What causes the Moon’s changing

appearance How the Sun lights the Moon’s surface How we see that surface from Earth

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Activity—Questions for review Would you see a full moon in the middle of

the afternoon? Explain your answer. Would you see a first-quarter moon just

before sunrise? Explain your answer. Why can’t you ever see a new moon?

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In the small circles draw what the Moon looks like from Earth at each of the Moon’s eight phases.

Activity—Test yourself

Sun

The Cosmic Landscape Lesson 3: Prehistoric Astronomy, Part 2 11

Summary What can we observe today about the

Moon that prehistoric people also would have seen?

How can we explain the Moon’s changing appearance?

The Cosmic Landscape Lesson 3: Prehistoric Astronomy, Part 2 12

NextDone—how prehistoric people used the sky to understand the seasons and navigate the worldNext—how certain people developed classical theories about the heavens