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A Greek astronomer and philosopher who lived around 350 B.C., suspected that Earth was spherical. He observed that Earth cast a curved shadow on the Moon durning a eclipse.
occurs when the Moon moves directly between the Sun and Earth and casts its shadow over part of Earth
when Earth's shadow falls on the Moon, a lunar eclipse occurs and a lunar eclipse begins when the Moon moves into Earth' s penumbra
South Pole Aiken Basin
the largest basin in the solar system and it is 2,500 kilometers under ground and 12 kilometers deep.
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