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The study of the moon, stars, and other objects in space


An imaginary line that passes through a planet's center and its North and South Poles, about which the planet rotates.


The spinning motion of a planet about its axis.


The movement of an object around another object.


The path of an object as it revolves around another object in space


The two days of the year on which the noon sun is directly overhead at either 23.5 degrees South or 23.5 degrees North.


The two days of the year on which neither hemisphere is tilted toward or away from the sun.

vernal equinox

The day of the year that marks the beginning of spring in the northern hemisphere.

autumnal equinox

The day of the year that marks the beginning of fall in the Northern hemisphere.


One of the different shapes of the moon as seen from Earth.


The partial or total blocking of one object in space by another.

solar eclipse

The blocking of sunlight to earth that occurs when the moon is directly between the sun and earth.


The darkest part of a shadow.


The part of a shadow surrounding the darkest part.

lunar eclipse

The blocking of sunlight to the moon that occurs when Earth is directly between the sun and moon.


The rise and fall of the level of water in the ocean. Mainly caused by the gravity of the moon, but the sun does have some effect.


Used for photographing and communication.

geosynchronous orbit

The orbit of a satellite that revolves around Earth at the same rate that Earth rotates.

space station

Used for scientific research.


A round pit on the moon's surface.

multi stage rocket

Allowed man to travel into space

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