Transcript Unit 1: Chemical Building Blocks Chapter 1: Introduction

Unit 4: Astronomy
Chapter 12: Earth, Moon, & Sun
Big Idea: The motions of Earth & the
moon & their position relative to the
sun result in day & night, the seasons,
phases of the moon, eclipses, & tides
4 Sections
1.
2.
3.
4.
Earth in Space
Gravity & Motion
Phases, Eclipses, & Tides
Earth’s Moon
Mrs. Lee - Ch 12
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Sec 1: Earth in Space
KEY CONCEPTS
• Earth moves through space in 2 major
ways:
1) rotation
2) revolution
• Earth has seasons because its axis is tilted
as it revolves around the sun
Mrs. Lee - Ch 12
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Sec 1: Key Terms
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Astronomy
Rotation
Orbit
Solstice
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Axis
Revolution
Calendar
Equinox
Mrs. Lee - Ch 12
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Sec 2: Gravity & Motion
KEY CONCEPTS
• The strength of the force of gravity between 2
objects depends on 2 factors:
1) the masses of the objects
2) the distance between them
• Newton concluded that 2 factors:
1) inertia
2) gravity
combine to keep Earth in orbit around the sun &
the moon in orbit around
Earth
Mrs. Lee - Ch 12
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Sec 2: Key Terms
• Force
• Gravity
• Law of universal
gravitation
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Mass
Weight
Inertia
Newton’s 1st law of
motion
Mrs. Lee - Ch 12
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Sec 3: Phases, Eclipses, & Tides
KEY CONCEPTS
• The changing relative positions of the moon,
Earth, & sun cause the phases of the moon,
eclipses, & tides
• The phase of the moon you see depends on how
much of the sunlit side of the moon faces Earth
When the moon’s shadow hits Earth or Earth’s
shadow hits the moon, an eclipse occurs
• When the moon’s shadow hits Earth or Earth’s
shadow hits the moon, an eclipse occurs
Mrs. Lee - Ch 12
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Sec 3: Phases, Eclipses, & Tides
(cont’d)
• A solar eclipse occurs when the moon
passes directly between Earth & the sun,
blocking sunlight from Earth
• During a lunar eclipse, Earth blocks
sunlight from reaching the moon
• The tides are caused mainly by differences
in how much the moon’s gravity pulls on
the different parts of Earth
Mrs. Lee - Ch 12
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Sec 3: Key Terms
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Phase
Solar eclipse
Penumbra
Tide
Neap tide
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Eclipse
Umbra
Lunar eclipse
Spring tide
Mrs. Lee - Ch 12
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Sec 4: Earth’s Moon
KEY CONCEPTS
• Features on the moon’s surface include maria,
craters, & highlands
• The moon is dry & airless. Compared to Earth,
the moon is small & has large variations in its
surface temperature
• Scientists theorize that a planet-sized object
collided with Earth to form the moon
Mrs. Lee - Ch 12
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Sec 4: Key Terms
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Telescope
Maria
Crater
Meteoroid
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