Astronomers found the remains of his rings of Saturn moon

Astronomers from France and the U.S. concluded that the rings of Saturn are the remnants of the satellite destroyed in a collision with another space object. The work of scientists, pre-print (pdf) which presented on the site arxiv.org, explains why Saturn is the only giant-planet solar system, "owns" the rings.

In astronomy, there are two competing theories circulated to explain how it acquired the ring of Saturn. The first assumes that the rings are the remnants of other comets with a friend. The second theory, forming a ring particles formed after the destruction of the moon of Saturn. Both scenarios are possible if in the past in our galaxy, there was strong activity of comets (a fact confirmed by many observations). The authors of this paper tried to evaluate the intensity of comets "traffic" during the late heavy bombardment - the period of high activity comets about 3.8 - 4.1 billion years ago.

The researchers concluded that during the late heavy bombardment of comets "ram" Saturn with intensity, making the two likely scenarios. More detailed calculations have shown that if events develop according to the first theory, a similar ring system were formed and the other planets giants. If true second option, apart from the rings of Saturn in theory could get only Jupiter.

Late heavy bombardment took place after 700 million years after the formation of Saturn. At that time, hypothetical satellites has been accessed on the planet orbits stationed inside the Roche limit - the maximum distance, which is closer to planetary satellites are destroyed under the effect of gravity on small particles. As a result of a collision with a comet satellite collapsed, the resulting pieces are on the "right" distance in order to continue to turn around Saturn and not be lost in space.

Calculations researchers have shown that if the other planets of the solar system at the time of education have satellites that are within the limit Rocha, by the early period of late heavy bombardment, they would be branded a planet or a left from their orbits. Only Saturn because of its rapid rotation has managed to keep the satellite on the "right" distance.

Despite the fact that the rings of Saturn are a "favorite" objects to study, astronomers can not clearly explain not only their origins, but also age. Until recently it was thought that the rings formed from 10 to 100 million years ago, but at the end of September came out work, which the authors argue that the age of the rings is not less than four billion years.