Chapter Chapter 2020EarthEarth

Sun Sun

MoonMoon

Lesson 1Lesson 1

Earth rotates on a tilted imaginary axis Earth rotates on a tilted imaginary axis and orbits the sunand orbits the sun

Earth’s rotation causes day and nightEarth’s rotation causes day and night Earth’s gravity pulls objects toward the Earth’s gravity pulls objects toward the

center-south is down everywherecenter-south is down everywhere About half the Earth is in sunlight while About half the Earth is in sunlight while

the other half is dark the other half is dark

Earth’ tilt and orbit cause Earth’ tilt and orbit cause seasonsseasons

Earth’s rotation defines day and nightEarth’s rotation defines day and night Earth’s orbit defines seasonsEarth’s orbit defines seasons Earth makes one revolution around the Earth makes one revolution around the

sun a year (365 days-12 months)sun a year (365 days-12 months) Earth’s orbit is not a perfect circleEarth’s orbit is not a perfect circle

Seasonal Patterns Seasonal Patterns

Hemisphere is half of the globe (northern Hemisphere is half of the globe (northern and southern)and southern)

Patterns of temperature and weather Patterns of temperature and weather trends change throughout a year and are trends change throughout a year and are called seasons (summer, winter, fall, called seasons (summer, winter, fall, spring)spring)

Equinox vx Solstice Equinox vx Solstice

September Equinox-Sun shines equally September Equinox-Sun shines equally on 2 hemispheres-Fall/Springon 2 hemispheres-Fall/Spring

December Solstice-North leans away December Solstice-North leans away from sun-Winter/Summer (shortest day)from sun-Winter/Summer (shortest day)

March Equinox-Sun shines equally on 2 March Equinox-Sun shines equally on 2 hemispheres-Spring/Fallhemispheres-Spring/Fall

June Solstice-North leans toward sun-June Solstice-North leans toward sun-Summer/Winter (longest day)Summer/Winter (longest day)

Length of DaysLength of Days

The farther you get away from the The farther you get away from the equator, the more extreme changes in equator, the more extreme changes in day and nightday and night

The closer you get to the equator, the The closer you get to the equator, the more equal amounts of time in day and more equal amounts of time in day and nightnight

On equator=12 day 12 night hoursOn equator=12 day 12 night hours On poles=20+ day/6 months changes On poles=20+ day/6 months changes

Angles of SunlightAngles of Sunlight

When the sun is high in the sky (directly When the sun is high in the sky (directly above you), the sunlight is concentrated above you), the sunlight is concentrated in one area-right angle-shadows are in one area-right angle-shadows are short- between 10 and 2short- between 10 and 2

When the sun is low in the sky, the When the sun is low in the sky, the sunlight strikes the ground at an obtuse sunlight strikes the ground at an obtuse or acute angle-not concentrated-shadows or acute angle-not concentrated-shadows are long-early morning or late afternoon are long-early morning or late afternoon

Lesson 2 Lesson 2

The moon is Earth’s natural satelliteThe moon is Earth’s natural satellite The moon rotates once per orbit of EarthThe moon rotates once per orbit of Earth Gravity keeps the moon in orbitGravity keeps the moon in orbit The moon is Earth’s closest neighborThe moon is Earth’s closest neighbor It takes astronauts 3 days of travel to It takes astronauts 3 days of travel to

reach the moonreach the moon

Moon’s craters show Moon’s craters show historyhistory

Mare-dark area on the moonMare-dark area on the moon Lunar means moonLunar means moon All the features that can be seen on the All the features that can be seen on the

moon are different types of solid or moon are different types of solid or broken rockbroken rock

Moon has no air, no oceans, no clouds, Moon has no air, no oceans, no clouds, no lifeno life

Craters Craters

Light colors designate high altitude-Light colors designate high altitude-highlandshighlands

Have many round features called craters Have many round features called craters that formed when small objects from that formed when small objects from space hit the surfacespace hit the surface

Moon’s lighted side has many large dark Moon’s lighted side has many large dark colored spotscolored spots

Moon’s dark side has mostly highlands Moon’s dark side has mostly highlands

Moon Rocks Moon Rocks

Different ages (some 4.5 billion years)Different ages (some 4.5 billion years) The older rocks are found in the The older rocks are found in the

highlandshighlands The new rocks are found in the dark The new rocks are found in the dark

maria areasmaria areas Rock covers the entire moon surfaceRock covers the entire moon surface Basalt is a common rock on the moonBasalt is a common rock on the moon

Layers of the MoonLayers of the Moon

Remains mostly unchanged for billions of Remains mostly unchanged for billions of yearsyears

Structure: Crust, mantle and coreStructure: Crust, mantle and core Similar materials in Earth and the moon Similar materials in Earth and the moon

but in different proportionsbut in different proportions Evidence from rocks show that the moon Evidence from rocks show that the moon

was once closer to Earth (3.8 cm yearly)was once closer to Earth (3.8 cm yearly)

Lesson 3Lesson 3

Positions of the Sun and Moon affect Positions of the Sun and Moon affect EarthEarth

EclipseEclipse TidesTides

Waxing vs Waning Waxing vs Waning Phases-orbits the Earth monthlyPhases-orbits the Earth monthly

Waxing and WaningWaxing and Waning

Waxing is1-2 week of the monthWaxing is1-2 week of the month Waning is 3-4 week of the monthWaning is 3-4 week of the month New moon-when the Earth, moon and New moon-when the Earth, moon and

sun are all lit in the same directionsun are all lit in the same direction Full moon-half way through cycle/month Full moon-half way through cycle/month

when the whole near side of the moon is when the whole near side of the moon is in sunlight-the moon and sun are in in sunlight-the moon and sun are in opposite directions (p. 701)opposite directions (p. 701)

Waxing means growing and waning Waxing means growing and waning means shrinkingmeans shrinking

The appearance of the moon depends on The appearance of the moon depends on the positions of the sun, moon, and Earththe positions of the sun, moon, and Earth

Crescent and Gibbous Crescent and Gibbous

Crescent moons occur when the moon Crescent moons occur when the moon appears close to the sun in the sky-appears close to the sun in the sky-visible during daytime or around sunrise visible during daytime or around sunrise or sunsetor sunset

Gibbous and full moons appear far from Gibbous and full moons appear far from the sun in the sky-more noticeable at the sun in the sky-more noticeable at nightnight

Lunar eclipseLunar eclipse

Moon becomes dark during a lunar Moon becomes dark during a lunar eclipse because it passes through eclipse because it passes through Earth’s shadowEarth’s shadow

Just before a lunar eclipse, sunlight Just before a lunar eclipse, sunlight streaming past Earth produces a full streaming past Earth produces a full moonmoon

A total lunar eclipse occurs when the A total lunar eclipse occurs when the moon passes completely into shadowmoon passes completely into shadow

Solar Eclipse Solar Eclipse

Solar eclipse occurs when the moon Solar eclipse occurs when the moon passes directly between the Earth and passes directly between the Earth and sunsun

The sun seems to darken because the The sun seems to darken because the moon’s shadow falls onto part of Earthmoon’s shadow falls onto part of Earth

Moon covers the sun and the sky Moon covers the sun and the sky becomes as dark as night becomes as dark as night

Do not ever look at a solar eclipseDo not ever look at a solar eclipse

Ocean Tides Ocean Tides

Average ocean water level rises slowly Average ocean water level rises slowly for about 6 hours to high tidefor about 6 hours to high tide

Then it lowers for about 6 hours to low Then it lowers for about 6 hours to low tidetide

Entire pattern takes about 24 hours Entire pattern takes about 24 hours 2 high and 2 low tides per day2 high and 2 low tides per day

Tides Tides

Tides occur because the moon’s gravity Tides occur because the moon’s gravity changes the shape of Earth’s oceanschanges the shape of Earth’s oceans

Moon pulls on different parts of Earth Moon pulls on different parts of Earth with different amounts of forcewith different amounts of force

Earth’s crust is hard enough to resist Earth’s crust is hard enough to resist being pulled into a different shape, but being pulled into a different shape, but Earth’s oceans do change shapeEarth’s oceans do change shape

Tides Tides

Moon’s pull produces a bulge of thicker Moon’s pull produces a bulge of thicker ocean water on the side of Earth nearest ocean water on the side of Earth nearest to the moon (picture on page 706)to the moon (picture on page 706)

Another bulge of water is produced on Another bulge of water is produced on the side of Earth farthest from the moon the side of Earth farthest from the moon because the moon pulls the center of because the moon pulls the center of Earth away from that sideEarth away from that side

Thin layers of water run in between bulgeThin layers of water run in between bulge

Chapter Review page 709Chapter Review page 709

Earth rotates on a tilted axis and orbits Earth rotates on a tilted axis and orbits the sun (day/night and seasons)the sun (day/night and seasons)

Moon is Earth’s natural satellite with Moon is Earth’s natural satellite with many similar characteristics as Earthmany similar characteristics as Earth

Positions of the sun and moon affect Positions of the sun and moon affect EarthEarth

Time to test …..Time to test …..

Study vocabulary and pictures noted Study vocabulary and pictures noted throughout the chapter throughout the chapter

Keep notes neat and organized in binderKeep notes neat and organized in binder Complete and study chapter review on Complete and study chapter review on

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