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axis an imaginary line around which the earth spins
core the central part of the sun
corona the outermost part of the sun's atmosphere
crater a bowl-shaped hole on the moon
day the complete rotation of Earth on its axis; 24 hours; the daylight hours
Earth the third planet from the sun in the solar system
ellipse an oval shape
gravity the force that keeps planets in orbit around the sun and governs the rest of the motion in the solar system
lunar eclipse when the Earth passes between the moon and the sun, casting a shadow on the moon
mare smooth places on the surface of the moon
moon a celestial body that revolves around a planet
night the time from dusk to dawn when no sunlight is visible
orbit the path the moon, planets, asteroids, and comets follow as they travel around the sun
penumbra the outside fringe of the shadow cast by Earth during a lunar eclipse
Created by: AHoldeman
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