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The Autumnal equinox marks the point in the calendar at which the length of night and the length of day are equal.
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At noon the sun is directly above the Equator (0°), and at other location, the angle of the Sun is equal to the latitude of this location. We use those obesvations to calculate the circumference of the Earth.
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Garmisch-Partenkirchen
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Dnipro
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Lafrançaise
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Dorohoi
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Ilion
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