Galileo Galilei made the discovery of several moons that can be found in the vicinity of the planet Jupiter, but one of them is the one that represents the greatest interest to astronomers due to the conditions that can be found in it.
Callisto is the name of the moon that is most interesting from the scientific field, because it is possible to find an ocean and that the distance with which it is with Jupiter, is adequate for the radiation does not affect at lethal levels to its surface and therefore in that satellite life can be formed.
In the year of 1610, Galileo Galilei made the observation of 4 moons that were near Jupiter, these moons are known today as "The Galilean satellites", which have the name Io, Europa, Ganymede and the most interesting of all Callisto, at a time when it was believed that the planet earth was the center of the solar system and therefore all the planets revolved around it, the observation and discovery of these 4 satellites, I help to understand much more our solar system and it was established that planets revolve around the sun.
Let's focus on Callisto, this satellite has an approximate diameter of 4800 kilometers, this being the second largest satellite of those around Jupiter and only being surpassed by Ganymede, which has a diameter of approximately 5260 kilometers. Callisto is also the third largest satellite in the solar system and is composed of rocky material, ice and ammonia. This moon of Jupiter is located at a distance of about 1,880,000 kilometers from its planet, Callisto has a circular orbit, therefore it is the satellite that is farthest from Jupiter. Something that characterizes Callisto, is that it is cataloged as an inert satellite because its surface does not present volcanic activities, therefore this is one of the moons with the largest craters in the solar system. Speaking of its surface, it is composed of 50% of frozen water and materials such as magnesium, iron with hydrated silicates, carbon dioxide, among other materials.
As I said at the beginning, there is a possibility that in Callisto there could be an ocean of approximately 60 and 200 kilometers deep, that ocean could have been formed as a result of the presence of radioactive elements and ammonia. One of the points for which it is believed that there could be an ocean of such size in Callisto, is that the magnetic field generated by Jupiter does not cross the surface of the satellite, therefore according to this theory, a layer could have formed in Callisto. of conductive liquid and given that possibly this water also contains ammonia, since the satellite is composed of that element, the depth of this ocean would be around 200 to 350 kilometers.
A curious fact of this Satellite, that like other stars, planets or galaxies that we can find in the immensity of the universe, its name (Callisto) comes from ancient Greece and comes from exactly one of the lovers who had the god Zeus. Callisto was the daughter of the king of Arcadia, later Callisto was pregnant of Zeus, reason why the god turned it into a bear and put it in the sky, since being there it would protect it of the fury of the wife of Zeus, Hera. Later Callisto, was assassinated by Artemisa.
Although in Callisto it is very unlikely that we can find life, of all the satellites belonging to Jupiter, it is the most likely to form life, whatever the case, the possible missions that will be done in the future, will give us ideas and more accurate information about the nature and formation of this moon.
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