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The imaginary vertical line that cuts through the center of Earth and around which Earth spins
An elongated circle, or oval shape, the shape of the planets orbit.
Half of the earth usually referred to as eastern or western; northern or southern
Earth's yearlong elliptical orbit around the sun
Spinning of Earth on its imaginary axis, which takes about 24 hours to complete and causes day and night to occur
Twice-yearly time each spring and fall when the Sun is directly over the equator and the number of daylight and nighttime hours are equal worldwide
An imaginary circle around the middle of the earth, halfway between the North Pole and the South Pole
The numbering system used to indicate the location of parallels drawn on a globe and measuring distance north and south of the equator
The numbering system used to indicate the location of meridians drawn on a globe and measuring distance east and west of the prime meridian (0°).
The path an object follows as it revolves around another object
a bowl-shaped depression formed by the impact of a meteorite
dark-colored, relatively flat regions of the Moon formed when ancient lava reached the surface and filled craters on the moon's surface
tall mountain ranges and appear as light areas on the moon
a meteoroid that strikes the surface of a moon or planet
a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy
the earth's tilt
(of the moon) pertaining to the period during which the visible surface of the moon increases
(of the moon) pertaining to the period during which the visible surface of the moon decreases
(used of the moon) more than half full
phase that occurs when all of the Moon's surface facing Earth reflects light
Polish astronomer who produced a workable model of the solar system with the sun in the center (1473-1543)
Italian astronomer and mathematician who was the first to use a telescope to study the moon and stars
highest tidal range that occurs to the alignment of Earth, the moon, and the sun
a tide with the least difference between high and low tide that occurs when the sun and moon pull at right angles to each other
the earth interrupts light shining on the moon
the moon interrupts light from the sun