Callisto (moon)

Callisto is the third-largest moon in the Solar System after Ganymede and Saturn’s largest moon Titan. It is the fourth Galilean moon of Jupiter by distance, with an orbital radius of about 1883000 km. Investigation by the Galileo spacecraft revealed that Callistso may have a small silicate core and possibly a subsurface ocean of liquid water at depths greater than 100  km.

About Callisto (moon) in brief

Summary Callisto (moon)Callisto is the third-largest moon in the Solar System after Ganymede and Saturn’s largest moon Titan. At 4821 km in diameter, Callisto has about 99% the diameter of the planet Mercury but only about a third of its mass. It is the fourth Galilean moon of Jupiter by distance, with an orbital radius of about 1883000 km. Investigation by the Galileo spacecraft revealed that Callistso may have a small silicate core and possibly a subsurface ocean of liquid water at depths greater than 100  km. The likely presence of an ocean leaves open the possibility that it could harbor life, but conditions are thought to be less favorable than on nearby Europa. Because of its low radiation levels, Callesto has long been considered the most suitable place for a human base for future exploration of the Jovian system. Callisti is named after one of Zeus’s many lovers in Greek mythology. The name was suggested by Simon Marius soon after its discovery by Galileo Galilei in 1610. The moon is surrounded by an extremely thin atmosphere composed of carbon dioxide and probably molecular oxygen, as well as by a rather intense ionosphere. Its surface is completely covered with impact craters, with no signs of plate tectonics or volcanism, and is thought to have evolved predominantly under the influence of impacts. It was discovered by Galileo in January 1610, along with the three other large Jovan moons—Ganymedede, Io, and Europa. It has been named after a nymph associated with the goddess of the hunt, Artemis, who was captured by Jupiter in secret by three young women who were honoured for their love for the planet in ancient times.

The suggestion was attributed to Johannes Kepler, but it has been suggested that it was actually the work of the Greek playwright Simon Marius, who wrote the play Calisto in the first century of the 20th century. The current name of the moon comes from the Greek word for nymphs, Calisto, which means “to love” or “to be loved” in Latin and means “love” in Greek and “nymphs” The moon has a density of about 1.83 gcm3, the lowest density and surface gravity of Jupiter’s major moons, and has a surface that may not be properly separated from the rest of the solar system. Its rotation is tidally locked to its orbit around Jupiter, so that the same hemisphere always faces inward. It’s less affected by Jupiter’s magnetosphere than the other inner satellites because of its more remote orbit, located just outside Jupiter’s main radiation belt. The surface is varied and made up of small, sparkly frost deposits at the tips of high spots, surrounded by a low-lying, smooth blanket of dark material. The absolute ages of the landforms are not known, and the age of the craters is not known. It does not show any signs that geological activity in general has ever occurred, and it is the oldest and most heavily cratered in the solar System.