Backward Lunar Orbits of Apollo 11 Addons

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Posts: 4
Joined: 14.11.2011
With us: 8 years 6 months

Backward Lunar Orbits of Apollo 11 Addons

Post #1by Langrenus » 19.11.2011, 00:53

I have a question involving orbits of certain add-on spacecraft.

Did the Apollo spacecraft, upon entering lunar orbit, approach the Moon from its western hemisphere, leading the Moon in its orbit around the Earth, or from its eastern hemisphere, trailing behind the moon in its orbit of Earth?

I have always thought it was the former, but the two Apollo spacecraft add-ons I have for Celestia tell the opposite story; they orbit in a counterclockwise direction, as seen from above the lunar North Pole. An approach to the lunar surface from that direction would have placed the sun right in the eyes of the astronauts as they prepared for landing.

Since both of my Apollo 11 add-ons seem to be orbiting in the wrong direction, my question is, can I change the parameters of the orbit in order to correct that? Otherwise, I am afraid my Apollo experience with Celestia, despite the beautiful graphics, will have lost all its charm.

Thank you to anyone who chooses to reply to my question.

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Re: Backward Lunar Orbits of Apollo 11 Addons

Post #2by selden » 19.11.2011, 17:44

A drawing of the trajectory of Apollo 11 and an animation of a "free return" orbit can be seen at

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