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0D-Earth-Moon-Sun
0D Earth-Moon-Sun
Term | Definition |
---|---|
revolve | A circular or elliptical path that an object travels around another object |
rotate | Spinning of an object on its imaginary axis |
near side | The side of the Moon that always faces Earth. This is the side that appears to change shape as the moon orbits the Earth. |
far side | The side of the Moon that never faces Earth – the “back” side of the moon – first photographed by USSR in 1959. |
lighted side | The portion of the moon that is reflecting light – appears to be illuminated. |
dark side | The portion of the moon that is NOT reflecting light – appears to be dark or invisible. |
terminator | the line the divides the lit and the unlit sides of the moon |
new moon | A phase of the Moon in which the side of the Moon that faces Earth is not illuminated at all. |
phase | The change in the sunlit area of one celestial body as seen from another celestial body. |
full moon | The phase of the moon in which the entire side of the Moon that faces Earth is fully illuminated. |
first quarter | The phase of the moon in which only the right half of the Moon's side that is facing Earth is illuminated. |
last quarter | The phase of the moon in which only the left half of the Moon's side that is facing Earth is illuminated. |
crescent | Literally a curved shape with pointed ends. The phase of the moon that is part way between a quarter moon and a new moon. Lighted side is less than half illuminated. |
gibbous | Literally means aving a hump or bump. The phase of the moon between a full moon and a quarter moon. Lighted side is more than half illuminated. |
waning | When the Moon appears to be getting smaller – the second half of the cycle |
waxing | When the Moon appears to get larger – the first half of the cycle |
direct light | Light that comes right from the source |
orbit | The curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution |
indirect light | light that has been reflected, diffused, or changed in some way |
axis | An imaginary line passing through the center of a planet(such as Earth) that the planet spins around. |
tilt | The angle by which the rotational axis of the Earth differs from a right angle to the orbital plane. |
eclipse | An obscuring of the light from one celestial body by either (1) the passage of another between it and the observer or (2) between it and its source of illumination (casting a shadow). |
gravity | a natural phenomenon by which all things with mass are brought toward one another (larger mass = more of this) |
lunar eclipse | When the Earth is in a straight line between the Moon and the Sun, causing the moon to appear dark due to the Earth's shadow. |
solar eclipse | When the moon is in straight line between the Sun and the Earth. The moon blocks the sunlight. |
season | A short period of climatic change in an area caused by the tilt of the Earth's axis as Earth revolves around the sun. |
equinox | Twice yearly time, each spring and fall, when the Sun is directly over the equator and the numbers of daylight and nighttime hours are equal worldwide. |
solstice | Twice yearly point at which the sun reaches its greatest distance north or south of the equator, marked by either the longest or shortest days |
tide | The periodic rise and fall of the water level in the oceans and other large bodies of water |
neap tide | the tide just after the first or third quarters of the moon where there is the least difference between high and low water |
spring tide | a tide just after a new or full moon, when there is the greatest difference between high and low water |