In 1992, a NASA team began a project called Spaceguard
Chapter 13, Problem 13.1.192(choose chapter or problem)
In 1992, a NASA team began a project called Spaceguard Survey, calling for an international watch for comets that might collide with Earth. Why is it more difficult to detect a possible doomsday comet with a hyperbolic orbit than one with an elliptical orbit?
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