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The Ring of Charon (First Book of the Hunted Earth)
The Ring of Charon - First Book of the Hunted Earth Author:Roger MacBride Allen SF Book Club edition. — While running an unauthorized experiment in gravity control, Larry activates the human-created mechanical Ring around Pluto's moon, Charon, and inadvertantly sets off a terrifying chain of events. Because the resulting gravity beam is detected by an alien spy--a half-organic, half-mechanical being who has been waiting for... more » eons, undetected, in the heart of Earth's moon.
Following a program instilled in it ages before, the alien responds. And suddenly Earth disappears!
Where has the planet and it's population gone? Can the remaining humans, scattered throughout the Solar System, locate and reclaim their mother world? Or will they, too, find themselves powerless to defeat the unknown aliens and destined to share Earth's mysterious fate?« less