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Chapter 30 – vocabulary Quiz – Define termsChapter 30 – vocabulary Quiz – Define terms

1.1. CratersCraters

2.2. RaysRays

3.3. ApogeeApogee

4.4. PerigeePerigee

5.5. MariaMaria

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Essential Question:Essential Question:Compare the Galilean moons and the rings of Compare the Galilean moons and the rings of Jupiter with the moons and rings of the other Jupiter with the moons and rings of the other

outer planetsouter planets

Warm Up : Warm Up : Explain how we ended up with our modern Explain how we ended up with our modern calendar.calendar.

Exit Task: Exit Task: compare the rings of Jupiter to the rings of compare the rings of Jupiter to the rings of SaturnSaturn

HomeworkHomework• Study for chapter 30 testStudy for chapter 30 test

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Vocabulary Chapter 30, define & one factVocabulary Chapter 30, define & one fact

1.1. MariaMaria

2.2. RillesRilles

3.3. CratersCraters

4.4. RaysRays

5.5. ApogeeApogee

6.6. PerigeePerigee

7.7. EclipseEclipse

8.8. UmbraUmbra

9.9. PenumbraPenumbra

10.10. Solar eclipseSolar eclipse

11.11. Lunar eclipseLunar eclipse

12.12. New moonNew moon

13.13. WaxingWaxing

14.14. Full moonFull moon

15.15. WaningWaning

16.16. EarthshineEarthshine

17.17. CalendarsCalendars

18.18. DayDay

19.19. MonthMonth

20.20. Solar yearSolar year

21.21. Julian calendarJulian calendar

22.22. Leap yearLeap year

23.23. Gregorian calendarGregorian calendar

24.24. Galilean moonsGalilean moons

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List the five kinds of lunar List the five kinds of lunar surface featuressurface features

Highlands Highlands composed of light colored rockcomposed of light colored rock Dark areas called Dark areas called MariaMaria (dark solidified (dark solidified

lava), that reflect little light. lava), that reflect little light. RillesRilles are areas that look like river beds are areas that look like river beds

where lava once flowedwhere lava once flowed Craters Craters are bowl shaped depressions, are bowl shaped depressions,

most were formed 4 billion years ago.most were formed 4 billion years ago. RaysRays is displaced materials from more is displaced materials from more

recent impacts that extend radially from recent impacts that extend radially from the impact site.the impact site.

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Describe the interior of the moonDescribe the interior of the moon

The side of the moon that faces Earth the crust The side of the moon that faces Earth the crust is 60km thick.is 60km thick.

The side away from the Earth is up to 100km The side away from the Earth is up to 100km thick.thick.

Beneath the crust is the mantle, which goes to Beneath the crust is the mantle, which goes to a depth of 1000 km and probably rich in silica, a depth of 1000 km and probably rich in silica, magnesium and ironmagnesium and iron

The moon may have a small iron core with a The moon may have a small iron core with a radius less than 700 kmradius less than 700 km

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Summarize the four stages in the Summarize the four stages in the development of the moon.development of the moon.

Stage 1Stage 1• The giant-impact hypothesis: says that a The giant-impact hypothesis: says that a

Mars sized object struck the earth in the early Mars sized object struck the earth in the early history of the solar system. Materials were history of the solar system. Materials were ejected from this collision which formed the ejected from this collision which formed the moon. moon.

Stage 2Stage 2• The moon was covered with an ocean of The moon was covered with an ocean of

molten rock. The densest sinking to the molten rock. The densest sinking to the center to form the core and the lighter rock center to form the core and the lighter rock forming the crust or outer layers. forming the crust or outer layers.

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Summarize the four stages in the Summarize the four stages in the development of the moon.development of the moon.

Stage 3Stage 3• The moon had cooled enough to form a thick crust The moon had cooled enough to form a thick crust

that covered the molten rock. Debris from the that covered the molten rock. Debris from the formation of the solar system struck the moon formation of the solar system struck the moon producing the cratered surface. Some of the producing the cratered surface. Some of the meteorites broke the crust and allowed molten rock meteorites broke the crust and allowed molten rock to flow to the surface to form Maria.to flow to the surface to form Maria.

Stage 4Stage 4• The final stage started 3 billion years ago after the The final stage started 3 billion years ago after the

moon had cooled and the debris from the early solar moon had cooled and the debris from the early solar system had decreased. All geologic activity has system had decreased. All geologic activity has stopped and meteors now cause a rayed impact. The stopped and meteors now cause a rayed impact. The moon has remain virtually unchanged for 3 billion moon has remain virtually unchanged for 3 billion years.years.

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Describe the orbit of the moon Describe the orbit of the moon around the earth.around the earth.

The moons orbit around the earth is an ellipse. The moons orbit around the earth is an ellipse. This means the distance from the earth variesThis means the distance from the earth varies

• when at it’s farthest point it is at apogee when at it’s farthest point it is at apogee

• the closest point is perigee. the closest point is perigee. The average distance is 384,000 km. The average distance is 384,000 km. The moon appears to rise and set with the earth The moon appears to rise and set with the earth

rotationrotation• but it is really moving 1/29but it is really moving 1/29thth the distance of the distance of

it’s orbit. it’s orbit. • This can be seen in the fact that it will rise This can be seen in the fact that it will rise

and set 50 minutes later each night.and set 50 minutes later each night.

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Explain why eclipses occur.Explain why eclipses occur. An eclipses occurs when a planetary body An eclipses occurs when a planetary body

passes through the shadow of another. passes through the shadow of another. There are two parts to the shadow There are two parts to the shadow

• the inner cone (called the umbra) blocks the the inner cone (called the umbra) blocks the sunlight completely. sunlight completely.

• The outer part of the shadow (called the The outer part of the shadow (called the penumbra) only partially blocks the light.penumbra) only partially blocks the light.

We see two types of eclipses, a We see two types of eclipses, a lunarlunar and a and a solarsolar

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Explain why eclipses occur.Explain why eclipses occur. Solar eclipseSolar eclipse• A solar eclipse is when the moon passes between the A solar eclipse is when the moon passes between the

earth and the sun. earth and the sun. • The moons shadow fall upon the earth. The moons shadow fall upon the earth. • People within the umbra will see a total eclipse and People within the umbra will see a total eclipse and

those in the penumbra but outside the umbra will see a those in the penumbra but outside the umbra will see a partial eclipse. partial eclipse.

• Because of the rotation of the earth, a total eclipse will Because of the rotation of the earth, a total eclipse will never last more then 7 minutes. never last more then 7 minutes.

• Sometimes an eclipse will occur when the moon is at Sometimes an eclipse will occur when the moon is at it’s apogee, this is called an annular eclipse and a line it’s apogee, this is called an annular eclipse and a line of sunlight can be seen around the edge of the moon. of sunlight can be seen around the edge of the moon.

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Explain why eclipses occur.Explain why eclipses occur.

Lunar eclipseLunar eclipse• This occurs when the moon passes This occurs when the moon passes

through the earth’s shadowthrough the earth’s shadow• A total eclipse occurs when the moon A total eclipse occurs when the moon

passes through the earth’s umbra passes through the earth’s umbra • A partial occurs when it passes through A partial occurs when it passes through

the penumbra. the penumbra. • They last several hours.They last several hours.

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Describe the phases of the Moon Describe the phases of the Moon

When the moon is between the sun and earth - new When the moon is between the sun and earth - new moon phase. moon phase.

Next a waxing-crescent phase. Next a waxing-crescent phase. Followed by a quarter moon Followed by a quarter moon Next waxing-gibbous phaseNext waxing-gibbous phase full moonfull moon After this it moves into the waning-gibbous phase and After this it moves into the waning-gibbous phase and

when it is a quarter or less it is in the waning-crescent when it is a quarter or less it is in the waning-crescent phase. phase.

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compare the Galilean moons & the compare the Galilean moons & the rings of Jupiter with the moons & rings of Jupiter with the moons & rings of the other outer planetsrings of the other outer planets

Explain How calendars are based on the Explain How calendars are based on the movements of the Earth and the moonmovements of the Earth and the moon

People would track time passage with the phases People would track time passage with the phases of the moon. of the moon.

In time these were converted into calendars. In time these were converted into calendars. There are three main parts days, months, and There are three main parts days, months, and

years. years. A day would measure the passage of one earth A day would measure the passage of one earth

rotation (24 hours). rotation (24 hours). A month would measure one complete moon A month would measure one complete moon

phase (29.5 days) phase (29.5 days) a year measure the time it takes the earth to a year measure the time it takes the earth to

complete one complete orbit around the sun complete one complete orbit around the sun (365.25 days).(365.25 days).

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Explain How calendars are based on the Explain How calendars are based on the movements of the Earth and the moonmovements of the Earth and the moon

Problems: a year of 365 days is too short and a Problems: a year of 365 days is too short and a 366 day is too long366 day is too long

so there must be a way to account for the ¼ day so there must be a way to account for the ¼ day in the year. in the year.

Second a 29 day month is too short and a 30 day Second a 29 day month is too short and a 30 day month is too long, the days of the month must month is too long, the days of the month must vary to account for this problem. vary to account for this problem.

Third, the moon orbits the earth between 12 to 13 Third, the moon orbits the earth between 12 to 13 times in a year, so the number of months can not times in a year, so the number of months can not correspond to the movements of the earth and correspond to the movements of the earth and moon and remain accurate.moon and remain accurate.

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Explain How calendars are based on the Explain How calendars are based on the movements of the Earth and the moonmovements of the Earth and the moon

The Julian calendar was the first to solve this The Julian calendar was the first to solve this problem. problem.

The year was divided into 12 months and eleven The year was divided into 12 months and eleven months had 30 or 31 days and February had 29. months had 30 or 31 days and February had 29.

Later 1 day was moved to August and the leap Later 1 day was moved to August and the leap year was added to keep the system balanced. year was added to keep the system balanced.

It did not take into account for the fact that they It did not take into account for the fact that they had estimated the year 11 minutes longer then it had estimated the year 11 minutes longer then it really is. This calendar lasted over 1500 years. really is. This calendar lasted over 1500 years.

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Explain How calendars are based on the Explain How calendars are based on the movements of the Earth and the moonmovements of the Earth and the moon

BY 1580 the calendar was about 10 days ahead of BY 1580 the calendar was about 10 days ahead of the seasons. the seasons.

To solve the problem Pope Gregory XIII ordered To solve the problem Pope Gregory XIII ordered ten days be dropped from October in 1582 and ten days be dropped from October in 1582 and that the Julian needed to be corrected. that the Julian needed to be corrected.

The solution was that every 400 years the The solution was that every 400 years the calendar needed to be 3 days shorter, so if the calendar needed to be 3 days shorter, so if the leap year ends in 00 and is not divisible by 400 leap year ends in 00 and is not divisible by 400 there is no leap and you must wait 4 years for the there is no leap and you must wait 4 years for the next leap year to occur. next leap year to occur.

The Gregorian is accurate to within 26 seconds The Gregorian is accurate to within 26 seconds and only needs to be adjusted every 3000 years. and only needs to be adjusted every 3000 years.

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Compare the characteristics of Compare the characteristics of the two moons of Marsthe two moons of Mars

Moons of Mars: Phobos and DeimosMoons of Mars: Phobos and Deimos Phobos completes an orbit in 7 hours and 40 Phobos completes an orbit in 7 hours and 40

minutesminutes Deimos completes an orbit in about 30 hoursDeimos completes an orbit in about 30 hours Irregular in shape: Phobos is 27km by 19km, Irregular in shape: Phobos is 27km by 19km,

Deimos is 15km by 11km Deimos is 15km by 11km Phobos has an 8km crater on it, both have Phobos has an 8km crater on it, both have

many craters suggesting they are old.many craters suggesting they are old. Both are smaller then a medium sized crater on Both are smaller then a medium sized crater on

our moonour moon

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Compare the Galilean moons and the rings of Jupiter Compare the Galilean moons and the rings of Jupiter

with the moons and rings of the other outer planetswith the moons and rings of the other outer planets.. Jupiter has rings that are 6,400 Jupiter has rings that are 6,400

km wide and less than 30 km km wide and less than 30 km thickthick

4 Galilean moons; IO, Europa, 4 Galilean moons; IO, Europa, Ganymede and Callisto.Ganymede and Callisto.

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Compare the Galilean moons and the rings of Jupiter Compare the Galilean moons and the rings of Jupiter

with the moons and rings of the other outer planetswith the moons and rings of the other outer planets.. All viewed by Galileo in 1610All viewed by Galileo in 1610 IO; is the closet to Jupiter, has active IO; is the closet to Jupiter, has active

volcanoes of sulfur, sulfur dioxide volcanoes of sulfur, sulfur dioxide atmosphere, giant iron core with a atmosphere, giant iron core with a magnetic field and red, orange and magnetic field and red, orange and yellow in coloryellow in color

Europa; second closest, covered in ice Europa; second closest, covered in ice 100 km thick, rock core and possible 100 km thick, rock core and possible waterwater

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Compare the Galilean moons and the rings of Jupiter Compare the Galilean moons and the rings of Jupiter

with the moons and rings of the other outer planetswith the moons and rings of the other outer planets.. Ganymede; third from Jupiter, low Ganymede; third from Jupiter, low

density, largest moon in the solar system, density, largest moon in the solar system, made of rock and ice, has valleys and made of rock and ice, has valleys and ridges, and has a magnetic field.ridges, and has a magnetic field.

Callisto; farthest from Jupiter, similar to Callisto; farthest from Jupiter, similar to Ganymede in size, density and Ganymede in size, density and composition, surface is the most cratered composition, surface is the most cratered in the solar system. in the solar system.

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Compare the Galilean moons and the rings of Jupiter Compare the Galilean moons and the rings of Jupiter

with the moons and rings of the other outer planetswith the moons and rings of the other outer planets.. Saturn; Rings are larger and brighter then Saturn; Rings are larger and brighter then

any other planet in solar system.any other planet in solar system. Each ring is divided into 100’s of ringlets. Each ring is divided into 100’s of ringlets. Size of rings 64,000 km wide and 200 Size of rings 64,000 km wide and 200

meters thickmeters thick Has 18 moons most small and icy, has 5 Has 18 moons most small and icy, has 5

large moons and Titan is largest at 5,000 large moons and Titan is largest at 5,000 km diameter.km diameter.

Titan has a thick nitrogen atmosphere. Titan has a thick nitrogen atmosphere.

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Compare the Galilean moons and the rings of Jupiter with Compare the Galilean moons and the rings of Jupiter with the moons and rings of the other outer planets.the moons and rings of the other outer planets.

Uranus has 20 small moons: the four largest are Uranus has 20 small moons: the four largest are Oberon, Titania, Umbriel, and Ariel – discovered Oberon, Titania, Umbriel, and Ariel – discovered in mid 1800’s. Miranda found in 1948 and the in mid 1800’s. Miranda found in 1948 and the rest after 1985 by Voyager 2, Has 11 small rest after 1985 by Voyager 2, Has 11 small ringsrings

Neptune has 8 moons: Triton and Nereid are Neptune has 8 moons: Triton and Nereid are largest, Triton has a retrograde orbit. Has a thin largest, Triton has a retrograde orbit. Has a thin set of ringsset of rings

Pluto has one moon Charon and completes one Pluto has one moon Charon and completes one orbit in 6.4 days, always over the same spot. orbit in 6.4 days, always over the same spot.

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Jupiter number of moonsnumber of moons 63 63 Saturn number of moonsnumber of moons 60 60 Uranus number of moonsnumber of moons 27 27 Neptune number of moonsnumber of moons 13 13 Pluto number of moonsnumber of moons 3 3