I remember an old science fiction movie in which there was another Earth in an orbit just opposite the Sun. Well, we do have a companion, but rather than a twin, it's more a little brother.

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Everything I need to know I learned through Googling.

Or maybe Cruithne's little brother.

Journey to the Far Side of the Sun, a Gerry Anderson film, precursor to U.F.O. and Space:1999.

little brother? Heh, yeah I'd say so, emphasis on little. Not a threat to our planet of course, in spite of the fact of sharing an orbit.

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The only reason for time is so that everything doesn't happen at once.
--Albert Einstein

Not in "Super-Marionation," then.

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Everything I need to know I learned through Googling.

Could 2002 AA29 be used as a sort of waystation to the other planets at all? Assuming that it could be nudged into a stable orbit with the earth, is there any chance that we might be able to use it's miniscule gravity as a stopover point for missions? (Probably not, but it never hurts to ask.)

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"Some see the glass half full, some see it half empty, and some see it crawling with toxic alien parasites who want to devour your pancreas." - Sgt Aarhus, from the book Ascending by James Alan Gardner