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"I identify with the weak person; this is one reason why my fictional protagonists are essentially antiheroes."
- Philip K. Dick

Free Return Trajectory  
  The idea that it would be possible for a projectile to go around the Moon and then return to Earth.  

It was the intent of the Baltimore Gun Club to actually hit the Moon with a projectile. However, upon missing the Moon the passengers began to debate upon the course of the projectile.

In watching the course of the projectile they could see that on leaving the moon it followed a course analogous to that traced in approaching her. It was describing a very long ellipse, which would most likely extend to the point of equal attraction, where the influences of the earth and its satellite are neutralized.

Such was the conclusion which Barbicane very justly drew from facts already observed, a conviction which his two friends shared with him.

"And when arrived at this dead point, what will become of us?" asked Michel Ardan.

"We don't know," replied Barbicane.

"But one can draw some hypotheses, I suppose?"

"Two," answered Barbicane; "either the projectile's speed will be insufficient, and it will remain forever immovable on this line of double attraction----"

"I prefer the other hypothesis, whatever it may be," interrupted Michel.

"Or," continued Barbicane, "its speed will be sufficient, and it will continue its elliptical course, to gravitate forever around the orb of night."

From From the Earth to the Moon, by Jules Verne.
Published by Various in 1867
Additional resources -

In writing the story the way he did, Verne became the first person to describe the idea of a free return trajectory, that is, a path that would lead from the Earth, around the Moon, and back to Earth again without any additional fuel expended for navigation.

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