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the region of the solar system most asteroids occupy; roughly between the orbits of Mars and Jupiter
Astronomical unit (AU)
the average distance between the Earth and the sun, or approximately 150,000,000 km
a small body of ice, rock, and cosmic dust loosely packed together that gives off gas and dust in the form of a tail as it passes close to the sun
the natural heating process of a planet, such as the Earth, by which gases in the atmosphere trap heat
the region of the solar system outside the orbit of Neptune that is occupied by small, icy, cometlike bodies
a unit of length equal to the distance light travels in space in 1 minute, or 18,000,000 km
a streak of light caused when a meteoroid or comet dust burns up in the Earth's atmosphere before it reaches the ground
"a spherical region of space that surrounds the solar system in which distant comets revolve around the sun"
Period of revolution
the time it takes for one body to make one complete orbit, or revolution, around another body in space
"the different appearances of the moon due to varying amounts of sunlight on the side of the moon that faces the Earth; results from the changing relative positions of the moon, Earth, and the sun"
the counterclockwise spin of a planet or moon as seen from above the planet's north pole
the clockwise revolution of a satellite around a planet as seen from above the north pole of the planet
the clockwise spin of a planet or moon as seen from above the planet's or moon's north pole
the percentage of your Earth weight you would experience on another planet; the weight you would experience on another planet
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