Earth-approach Asteroid

   An asteroid whose orbit crosses the Earth's orbit, or whose orbit is being changed by Earth's gravity, and will some day cross the Earth's orbit. There are two types of Earth-approach Asteroids. Apollo Asteroids, which cross the Earth's orbit at the present time, and Amor and Aten Asteroids, which do not cross the Earth's orbit at the present time.

The writer's dictionary of science fiction, fantasy, horror and mythology. 2014.

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