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an imaginary circle around the middle of the earth, halfway between the North Pole and the South Pole
One half of the Earth, north or south of the equator or west or east of the Prime Meridian.
An imaginary line passing through the Royal Observatory in Greenwich, England, which marks the 0° line of longitude.
International Date line
The line of longitude that marks where each new day begins, centered on the 180th meridian. Opposite prime Meridian
Tropic of Capricorn
an imaginary line of latitude located at 23.3 S. It marks the southern boundary of the earth's tropical zone.
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