The Ring of Charon is a science fiction book by American writer Roger MacBride Allen, first published in 1990 by Tor Books. It is the first in a series of three (although the third book has yet to be published) books under the name of The Hunted Earth. The story unfolds as an unknown alien race captures Earth with the use of a controlled wormhole, which was triggered accidentally by artificial gravity experiments issued from a human outpost in space. The story follows all three viewpoints: the Earth, the Solar System (sans Earth) and the alien race (Charonians). Characters Dr. Sondra Berghoff: A researcher at the Gravitics Research Station who assists Larry Chao in his attempts to prove his findings in artificial gravity. Without authorization, she reconfigures a routine experiment with Larry's assistance to boost the power of the gravity signal a thousandfold, resulting in the accidental awakening of the charonian Observer, also known as the Lunar Wheel. Wolf Bernhardt: Scientist at the Jet Propulsion Laboratory on Earth, who becomes the head of the UN Directorate of Spatial Investigation after the Big Jump. Larry O'Shawnessy Chao: A young junior researcher at the Gravitics Research Station on Pluto who discovers a way to concentrate and amplify the power of an existing source of gravity. Unfortunately, in a later attempt to prove his claims, he directs a modulated gravity beam at Earth, triggering its capture by the slumbering Observer buried deep within the moon. Dr. Gerald MacDougal: Husband to Marcia MacDougal. A born-again Canadian exobiologist, Gerald was transported to the Multisystem along with the Earth. Dr. Marcia MacDougal: Wife to Gerald MacDougal. Born in Tycho Purple Penal, she was declared a refugee and escaped the Naked Purple lifestyle when the fire department burned her parents' house. A planetary engineer at VISOR, Marcia observed Earth's disappearance and later cracked Charonian communications via the Arecibo method. Dr. Hiram McGillicutty: The abrasive head physicist at VISOR. Notorious for his lack of couth when dealing with other people, he is brilliant and meticulous in gathering data, even if he tends to come to the wrong conclusions. Dr. Simon Raphael: Embittered by years of failed research into gravity manipulation, Raphael is the director of the Gravitics Research Station. He initially dismisses Larry Chao's test results as a fabrication in attempt to keep the station open, and attempts to shut down further research into the so-called Chao Effect.