Eclipses and Motion of the MoonChapter 2
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Lunar Eclipse
The reddish light in the Earth’s umbra that allows the moon to be seen even during a Total Eclipse is due to the long visible waves being bent by the Earth’s atmosphere,
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Lunar EclipseDuring passage through the Earth’s shadow the Moon can encounter partial shadow, complete shadow or both during its transit
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Because the plane of the Earth’s a orbit and the plane of the Moon’s orbit are not the same, eclipses can occur only when the Sun, Moon and Earth are all on the same line or where the planes cross.
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Aristarcus of Samos (250 bc)Interested in eclipses
Studied everything he could findRecognized the geometrySun large and a long way awayMoon much smaller and nearer
Concluded Earth revolves around the SunEarth rotates on its axisMoon revolves around the Earth
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The Old Greeks
AristotlePhases of the Moon
HipparchusStar ChartsSystem of Stellar MagnitudePrecession
AristarcusSizes
ErotosthenesCircumference of the Earth
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Eclipses can occur only when the Sun, Moon and Earth are all on the same __________.
In Class Quiz