Ganymede is the largest moon in the Solar system
Probably in the entire Universe there is no planet or satellite with a perfectly smooth surface. And all because in space objects of constant flow of complex processes that can affect their appearance. These include all kinds of earthquakes, volcanoes and so on. Also the shape of planets and satellites changes when falling on them of celestial bodies of smaller size on their surfaces are formed impact craters. They are almost all known cosmic bodies with solid surface. To verify this, just look at the pictures of the moon, Mars and so on. You will see that they have circles of different sizes, most of which are the craters. Recently, Japanese scientists studied the pictures of Ganymede, which is considered one of the 79 satellites of Jupiter. It turned out that on its surface there is education, which may be the largest impact crater in the Solar system.
About the unexpected opening of the Japanese scientists was described in a scientific . If you look closely at the pictures of Ganymede, made on the spacecraft "Voyager-1 and Voyager-2" and "Galileo" in the period from 1979 to 2003, you notice that the satellite is composed of many randomly scattered bright and dark areas. Is considered, light areas are very young, but the dark territory was formed a very long time and currently covered with uneven left faced companion celestial bodies. Pictures of the surface of Ganymede, and to this day are causing scientists of great interest, so they are reviewing them regularly.
As you can see, Ganymede is actually composed of light and dark areas
In a recent study of the irregularities, the researchers noticed that the grooves on the satellite constitute a system of rings with a common center. Diameter of internal holes equals to 1380 km, and the diameter of the outer circle is 7800 miles. According to researchers, this structure could occur on the surface of Ganymede only after the fall of the asteroid. If the assumption is true of scientists discovered a system of rings is the largest impact crater in the Solar system. Here you have another interesting fact about space, which you can share with your friends.
As you know, Ganymede is almost the same size as Mars.
According to the researchers ' estimates, such a large crater could be formed only in case of a fall Ganymede celestial body with a diameter of 150 kilometers. While its speed had to be at least 20 kilometers per second. If we assume that such an event has taken place in the history of the Universe, it happened about four billion years ago. It is noteworthy that a powerful collision was bound to provoke great changes in the structure of the satellite. And they are just the same, there are.
Structure of Ganymede
It is believed that the insides of the satellite Ganymede have a complex structure, which at least consists of crust, mantle and core. And this despite the fact that a similar-sized moon of Jupiter called Callisto does not possess complex structure. Therefore, scientists believe that in the history of Ganymede has really been a serious event that seriously affected its structure. But the story of Callisto is relatively boring, so its structure is simple. The possibility of separating the innards of Ganymede on the crust, mantle and core during the natural evolution of a space object scientists believe it is unlikely.
Callisto, another moon of Jupiter
One of the few interesting moments in the history of the satellite Callisto can be considered a falling object which left a crater with a diameter of 3800 kilometers. Since the crater diameter is two times less than the formed pits on Ganymede, it is believed that Callisto has faced a much smaller heavenly body. But he could not provoke global changes on the surface of the crater.
It is Important to note that in the Solar system there are other large impact craters. For example, on Mars there is the plain of Utopia with a diameter of about 3,300 km. The largest impact crater on Earth is located near the African city Johannesburg — we are talking about the diameter of about 300 kilometers. There is also located in Antarctica crater in Wilkes Land with a diameter of 500 kilometers, but scientists do not yet believe that it was formed after the impact of a celestial object.