Astronomy Space Chapter 25: Earths Moon

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Astronomy / SpaceChapter 25 Earths Moon

• 25.1 Origin and Properties of the Moon
• 25.2 The Moons Motion

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25.1 Origin and Properties of the Moon

• Origin of the Moon
• What are the four theories about the moons
  origin?
• The moon once had volcanoes.
• Does it still?
• Why are there so many craters on the moon?

1. Formed with earth 2. It spun off the earth
3.Captured by the earth 4.Impact theory
NO
No atmosphere to protect and erode. No plate
tectonics to recycle.
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25.1 Origin and Properties of the Moon

• Properties and Features of the Moon
• The moon rotates at the same rate that it
  revolves. What does this mean?
• It has a diameter of 3476 km (about a 1/4 of the
  earths)
• Has about 1/18 the mass of earth
• Maria-Moon Basins

We always see the same side of the moon there
is a dark side.
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25.1 Origin and Properties of the Moon

• 5. Highlands-Moon mountains.
• 6. Rilles-Trench like valleys moving through the
  Maria.
• 7. Lunar Craters-Formed from impacts by
  meteoroids.
• 8. Lunar soil-Made up of debris of various sizes.

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25-2 The Moon's Motions

• The Moon's Orbit
• Rises in the east and sets in the west.
• Takes 27 1/3 days to complete its orbit.
• It sets 50 minutes later every day.

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25-2 The Moon's Motions

• B. The Moon Phases (page 563)
• Phases-Daily changes in the moon's appearance as
  viewed from earth.
• From dark to light waxing (2 weeks)
• From Light to dark waning (2 weeks)
• List and draw the phases from new to new below!

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25-2 The Moon's Motions

• Lunar Eclipse (page 564)
• Umbra-area of total shadow
• Penumbra-area of partial shadow
• Lunar Eclipse-an event during which Earth's
  shadow prevents the sunlight from reaching the
  moon.

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25-2 The Moon's Motions

• D. Solar Eclipse (page 565)
• Occurs when the moon comes between the sun and
  Earth and the moon's shadow hits Earth's surface.
• Occurs only at the new moon phase.