Luna,Luna,The The

MoonMoonCh 21.4Ch 21.4

The MoonThe Moon

Except for the Sun, the Moon affects us Except for the Sun, the Moon affects us more than any other celestial body…tides more than any other celestial body…tides & eclipses.& eclipses.

A few facts:A few facts:

Diameter: 3476 kmDiameter: 3476 kmDensity: 3340 kg/mDensity: 3340 kg/m33

Sidereal month: 27.32 days (one orbit Sidereal month: 27.32 days (one orbit about the Earth)about the Earth)

Rotates on its axis at the same rate as it Rotates on its axis at the same rate as it orbits the Earth.orbits the Earth.

Avg Distance from Earth: 384,400 km Avg Distance from Earth: 384,400 km (measured by lasers to reflectors on (measured by lasers to reflectors on Moon)Moon)

Phases of the MoonPhases of the Moon

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http://www.classzone.com/books/http://www.classzone.com/books/earth_science/terc/content/visualizations/earth_science/terc/content/visualizations/es2503/es2503page01.cfmes2503/es2503page01.cfm

Complete the phases of the moon diagramComplete the phases of the moon diagram

AnswersAnswers

Lunar EclipsesLunar Eclipses

Penumbra = shadow within which sunlight Penumbra = shadow within which sunlight is partially blockedis partially blocked

Umbra = shadow within which sunlight is Umbra = shadow within which sunlight is completely blocked (Total eclipses)completely blocked (Total eclipses)

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Lunar EclipsesLunar Eclipses

http://www.enchantedlearning.com/subjects/http://www.enchantedlearning.com/subjects/astronomy/moon/Lunareclipse.shtmlastronomy/moon/Lunareclipse.shtml

http://www.mreclipse.com/Special/LEprimer.html

Write a description of a lunar eclipse and label the diagram.

Lunar EclipseLunar Eclipse

Lunar Eclipse AnswersLunar Eclipse Answers

Solar EclipsesSolar Eclipses

Umbral shadow of the moon is only about Umbral shadow of the moon is only about 150 km wide where it reaches the earth150 km wide where it reaches the earth

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Solar EclipseSolar Eclipse

http://www.mreclipse.com/Special/SEprimer.html

http://www.enchantedlearning.com/subjects/astronomy/sun/solareclipses.shtml

Write a description of a solar eclipse and label the diagram.

Solar Eclipse AnswersSolar Eclipse Answers

Lunar SurfaceLunar Surface

Highlands = light colored rockHighlands = light colored rockMaria = dark areas, smooth, dark solid Maria = dark areas, smooth, dark solid

lava flows flooded the basinslava flows flooded the basinsRilles = deep channels perhaps caused by Rilles = deep channels perhaps caused by

volcanic activityvolcanic activityCraters = depressions from meteoroid Craters = depressions from meteoroid

impactsimpactsRays = displaced materialRays = displaced material

InteriorInterior

Seismologists look at seismographs and see Seismologists look at seismographs and see weak quakesweak quakes

4 seismometers were placed during 4 seismometers were placed during ApolloApollolandingslandings

Crust is thin on the side towards EarthCrust is thin on the side towards Earth Crust is thick on back sideCrust is thick on back side Perhaps has a small, partially molten metallic Perhaps has a small, partially molten metallic

corecore Little of no volcanic activity has taken place in 3 Little of no volcanic activity has taken place in 3

billion yearsbillion years

Chemical compositionChemical composition

Similar to the silicate rocks of the Earth’s Similar to the silicate rocks of the Earth’s crustcrust

Water is nearly absentWater is nearly absent

AtmosphereAtmosphere

The moon has a minimal atmosphere The moon has a minimal atmosphere since gases escape almost immediately. since gases escape almost immediately.

Other moonsOther moons MarsMars

Asteroids caught by Mar’s gravityAsteroids caught by Mar’s gravity JupiterJupiter

Io = volcanically activeIo = volcanically active SaturnSaturn

Frozen water with rocky materialFrozen water with rocky material UranusUranus

Ice, rock & heavily crateredIce, rock & heavily cratered NeptuneNeptune

Triton revolves in retrograde orbit & geologically activeTriton revolves in retrograde orbit & geologically active PlutoPluto

CharonCharon