 | Term | Definition |
| |
Axis |
An imaginary line that extends from the North Pole to the South Pole. |
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Rotation |
The spinning of the Earth on its axis. |
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Revolution |
The movement of one body in space around another body. |
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Orbit |
The path a body follows as it revovles around another body. |
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Perihelion |
The closest pt. of Earth's orbit to the Sun. |
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Aphelion |
The farthest pt. of Earth's orbit to the Sun. |
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Zenith |
The Sun's highest pt. in the sky, from the Earth. |
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Horizon |
The line where the Earth meets the sky. |
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Solstice |
When the noon sun is directly above 23 degrees north, or 23 degrees south. |
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Equinox |
The noon sun is directly above the equator. |
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Vernal Equinox |
The first day of spring in the Northern Hemmisphere. |
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Summer Solstice |
On the first day of summer, the sun is directly above 23 degrees north. It is the longest day and shortest night of the year. |
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Winter Solstice |
On the first day of winter, the noon sun is directly above 23 degrees south. It is the shortest day and the longest night of the year. |
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Autumnal Equinox |
The first day of fall, in the Northern Hemisphere. |
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Time Zone |
The distance Earth rotates in one hour. |
