Ganymede (moon) every orbit of Ganymede, Europa orbits twice and Io orbits four times. Conjunctions (alignment on the same side of Jupiter) between Io and Europa occur when Io is at periapsis and Europa at apoapsis. Conjunctions between Europa and Ganymede occur when Europa is at periapsis. The longitudes of the Io–Europa and Europa–Ganymede conjunctions change with the same rate, making triple conjunctions impossible. Such a complicated resonance is called the Laplace resonance. The current Laplace resonance is unable to pump the orbital eccentricity of Ganymede to a higher value. The value of about 0.0013 is probably a remnant from a previous
The Ganymede Club The Ganymede Club The Ganymede Club is a science fiction novel by American writer Charles Sheffield, published in 1995. A mystery and a thriller, the story unravels in the same universe that Sheffield imagined in "Cold as Ice". Shortly after humanity begins colonisation of the solar system, a trade war sets off vicious civil war that kills billions. The book received favorable reviews from "Library Journal" and "Kirkus Reviews", as well as in the science-fiction press. It was ranked #14 in SF novels in the 1996 "Locus" awards. The novel has been translated into Italian and was published as "Memoria