Europe
Europa is the smallest of the Galilean satellites (discovered by Galileo Galilei)
Europa is smaller than our moon. Its diameter is 3100 km, density is approximately 3.2 plus, minus 0.2 g/cm3. Its density is similar to that of Io and our Moon, and much denser than Ganymede and Calisto. Which indicates that Europe was formed under conditions in which Water was not concentrated.
Europa is mainly composed of silicates and metal oxides, with a moderate amount of volatiles. Since Io has about the same density, we can see how these 4 satellites are divided into 2 groups, and therefore the satellites will have the same groups if they are divided by water content. The moon Europa attracts very close attention of scientists, because under its thick icy crust, most likely, there is a vast ocean of water. And where is water, is there, perhaps, life?
