 | Term | Definition |
| |
axis |
an imaginary line that goes through an object |
| |
rotation |
the spinning of a planet, moon, or star around its axis |
| |
revolution |
the repeated motion of one object around another, much more massive object |
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orbit |
the path followed by one object as it revolves around another object, such as Earth's orbit around the Sun |
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ellipse |
an oval-shaped curve that is like a circle stretched out in opposite directions |
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eclipse |
a temporary situation in which an object in space casts its shadow on another object |
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lunar eclipse |
the passage of the Moon through Earth's shadow |
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solar eclipse |
the passage of the Moon between the Sun and Earth; the moon casts its shadow on Earth |
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constellation |
any one of 88 areas in the sky that are used to identify and name the stars |
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The Earth rotates on its axis. |
Night & day |
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The Earth revolves around the Sun. |
A year |
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The Earth's axis is tilted as it rotates. |
Seasonal changes |
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The moon rotates once on its axis as it revolves once around Earth. |
Phases of the Moon |
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The moon passes through the Earth's shadow. |
A lunar eclipse |
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The Earth passes through the Moon's shadow. |
A solar eclipse |
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Always moving |
Earth |
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The Earth rotates in this direction |
west to east |
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The Sun and other stars appear to move in this direction |
east to west |
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This keeps Earth revolving around the Sun |
gravity |
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The moon rotates this many times as it revolves once around Earth |
once |
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Crescent, quarter, and full moon are examples of these |
Phases of the moon |
