Callisto One of Jupiter's Moons
Callisto is one of the many moons of Jupiter and is very tolerant to Jupiter’s magnetosphere. It was discovered in 1610 by Galileo Galilei; it is the third largest moon in our solar system and is also the second largest in the Jovian system. Callisto has a 99% diameter of Mercury, but is only 1/3 its mass. Callisto is composed of rock and ices. Its surface is composed of water ice, carbon dioxide, silicates, and organic compounds; scientists have used the Galileo spacecraft and have revealed that Callisto may have a small silicate core or and possibly a subsurface ocean. Callisto has a heavily cratered surface and is extremely old. It does not show any evidence of plate tectonics or any signs of volcanoes, but it is thought to have evolved under the influence of a series of impacts it also has chains of very old craters.
Callisto has a very thin atmosphere that is composed of carbon dioxide, some scientists believe that Callisto could maintain life for life. It's daily orbit is approx. 16.7 Earth days; Callisto is approx. 4 billion years old. Callisto brings a great interests to many scientists. NASA's Galileo spacecraft even crashed into Callisto. Callisto's atmosphere where the outer edges is an intense ionosphere, radiation makes it impossible for humans to live on Callisto.
Callisto was named after one of Zeus's lovers; Callisto was a nymph, and associated with the daughter of the hunt also known as Artemis. Another name for this moon is Jupiter IV or the 4th satellite of Jupiter. Callisto is one of the outermost of the the 4 Galilean moons of Jupiter. Callisto is not involved with the mean- motion resonance which the three inner Galilean satellites in which they are locked. Callisto like many other moons it's rotation is locked to be on synch with its orbit. The inner parts of Callisto are made up of a salty underground ocean, rock, ices, and a small rocky core. It's surface features include a very battered surface, impact craters. Callisto is 3,100, 000 miles away from the sun. Callisto is not very much larger than our own moon.
Resources
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