Handout 27-3Handout 27-3The Inner PlanetsThe Inner Planets

11

The planets closest to the sun are called The planets closest to the sun are called the ____________________. the ____________________. inner planetsinner planets

22

Name the four inner planets Name the four inner planets MercuryMercuryVenusVenusEarthEarthMarsMars

33

The inner planets are also called The inner planets are also called ______________________ because they ______________________ because they are like Earthare like Earth.. terrestrial planetsterrestrial planets

44

Made mostly of solid rock with metallic cores.Made mostly of solid rock with metallic cores.

Describe the composition of the inner planets.Describe the composition of the inner planets.

55

Bowl-shaped depressions called Bowl-shaped depressions called _______________________ formed on _______________________ formed on the surfaces of inner planets when the the surfaces of inner planets when the planets collided with other objects in planets collided with other objects in space.space. impacts cratersimpacts craters

MercuryMercury

66

Mercury, the closest planet to the sun, Mercury, the closest planet to the sun, circles the sun every circles the sun every

B: 88 daysB: 88 days

77

Mercury rotates on its axis once everyMercury rotates on its axis once everyC: 59 days C: 59 days

88Mercury’s surface features a long line of Mercury’s surface features a long line of

cliffs andcliffs andB: a large number of cratersB: a large number of craters

99

The absence of a dense atmosphere and The absence of a dense atmosphere and Mercury’s slow rotation contribute to Mercury’s slow rotation contribute to

D: a large daily temperature rangeD: a large daily temperature range

VENUSVENUS

Phases of Venus seen from Earth

1010

How long is the orbital period of Venus, How long is the orbital period of Venus, the second planet from the sun?the second planet from the sun?

225 days225 days

1111How often does Venus rotate? How often does Venus rotate? Once every 243 daysOnce every 243 days

1212

The planet that Venus most resembles in The planet that Venus most resembles in mass, size, and density is mass, size, and density is ________________________. ________________________.

EarthEarth

1313

Venus’s atmospheric pressure is about Venus’s atmospheric pressure is about ___________ times the pressure on Earth.___________ times the pressure on Earth.

9090

1414

What two factors cause the high What two factors cause the high temperatures on Venus? temperatures on Venus?

It is close to the sunIt is close to the sunHigh amount of carbon dioxide in its High amount of carbon dioxide in its

atmosphereatmosphere

1515

What percentage of the atmosphere on What percentage of the atmosphere on Venus is composed of carbon dioxide? Venus is composed of carbon dioxide?

96%96%

1616

Venus appears to be very bright in the Venus appears to be very bright in the night sky because drops of night sky because drops of _________________________ form a _________________________ form a cloud layer that reflects sunlight. cloud layer that reflects sunlight.

Sulfur dioxideSulfur dioxide

1717

Why is Venus commonly referred to as the Why is Venus commonly referred to as the evening star evening star or or morning star?morning star?

It is usually visible from Earth only in the It is usually visible from Earth only in the morning or early evening.morning or early evening.

1818

The surface of Venus is composed of The surface of Venus is composed of which two types of rock? which two types of rock?

Basalt and graniteBasalt and granite

1919

19. 19. MagellanMagellan B: a U.S. satellite that collected data about Venus B: a U.S. satellite that collected data about Venus

2020

volcano volcano C. C. a landform commonly found on Venus a landform commonly found on Venus

2121

Maat Mons Maat Mons A. A. the highest volcano on Venus the highest volcano on Venus

EarthEarth

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Earth is the ________________ planet Earth is the ________________ planet from the sun. from the sun.

third (rock from the sun)third (rock from the sun)

2323

The orbital period of The orbital period of Earth is Earth is ______________ days.______________ days.

365 1/4365 1/4

2424

Earth completes one Earth completes one __________________ on its axis every __________________ on its axis every day. day.

rotationrotation

2525

How many moons does Earth have? How many moons does Earth have?

oneone

2626

Over the last ______________ years, Over the last ______________ years, Earth’s continents separated from a single Earth’s continents separated from a single landmass and drifted to their present.landmass and drifted to their present.

250 million250 million

2727

What two factors have caused the surface What two factors have caused the surface of Earth to keep changing? of Earth to keep changing?

Weathering and erosionWeathering and erosion

2828Why is Earth the only planet on which Why is Earth the only planet on which

water exists in a liquid state? water exists in a liquid state? Earth’s unique atmosphereEarth’s unique atmosphereDistance from sun allows water to exist in Distance from sun allows water to exist in

the liquid statethe liquid state

2929

How was Earth able to maintain the How was Earth able to maintain the moderate temperatures that were moderate temperatures that were necessary to support life?necessary to support life?

The oceans and atmosphere help Earth to The oceans and atmosphere help Earth to have moderate temperatures.have moderate temperatures.

3030

What three elements does Earth have in What three elements does Earth have in the proper combination necessary to the proper combination necessary to support life?support life?

Water, oxygen, and temperatureWater, oxygen, and temperature

MarsMars

3131Mars is the ____________________ Mars is the ____________________

planet from the sun.planet from the sun.

fourthfourth

3232

How long is Mars’s orbital period? How long is Mars’s orbital period?

687 days687 days

3333

How often does Mars rotate on its axis?How often does Mars rotate on its axis?

Every 24 hours and 37 minutesEvery 24 hours and 37 minutes

3434

Why are Mars’s seasons similar to Why are Mars’s seasons similar to Earth’s?Earth’s?

Its axis tilts at nearly the same angle as Its axis tilts at nearly the same angle as Earth’s.Earth’s.

3535

Mars is believed to have been geologically Mars is believed to have been geologically active because of its massive volcanoes active because of its massive volcanoes and a system of deep ________________ and a system of deep ________________ on its surface.on its surface.

canyonscanyons

3636

One of the many major volcanic regions One of the many major volcanic regions on Mars is called ___________________.on Mars is called ___________________.

Tharis MontesTharis Montes

3737

The largest volcano on Mars is The largest volcano on Mars is ___________________________, which ___________________________, which is three times the height of Mount Everest.is three times the height of Mount Everest.

Olympus MonsOlympus Mons

3838

Why do scientists think that Martian Why do scientists think that Martian volcanoes have grown so large? volcanoes have grown so large?

Mars does not have tectonic platesMars does not have tectonic plates

3939Two seismic wave-producing geological Two seismic wave-producing geological

events called _______________________ events called _______________________ indicate that indicate that volcanoes on Mars may volcanoes on Mars may still be active.still be active.

mars quakesmars quakes

The EndThe End