Recent content by lubi

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    Graduate Could Twin Planets Be Visible to Each Other in Altered Orbits?

    I met a question when I try to solve a twin-planet problem in "Classical mechanics" by Goldstein 3rd edition. Chap3-17. As followings: One of the classic themes of science fiction is a twin planet (“Planet X”) to Earth that is identical in mass, energy, and momentum but is located on the orbit...