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9 Cards in this Set

  • Front
  • Back
amount of time it takes a comet to complete an orbit
region of the earth's atmosphere which has harmful ultraviolet radiation filtering out
ozone layer
group of asteroids found in the inner solar system, many which cross paths with Earth
near earth asteroids
length of time it takes the earth to complete its revolution
365 1/4 days
pieces of space debris smaller than the smallest asteroids
completion of a moon's revolution
lunar month
little "planets" ranging in size from a few hundred miles across to the size of a house
the ocean at its lowest point on the shore
low tide
type of tide that occurs when the gravitational forces of the sun and the moon work against each other, resulting in weaker tides
neap tide