Enceladus

The astronomers of the university of Virginia discovered that Enceladus In the Greek mythology, Enceladus is the eponymic Giant, overcome by Athena during Gigantomachy (the war of the gods against the Giants), buried under the island of Sicily and the person in charge of volcanic eruptions of Etna. The name " Enceladus " as well as those of seven satellites of Saturn known about the time was suggested by John Herschel, the son of the discoverer William Herschel, in a publication of 1847.  , The sixth biggest moon of Saturn, pulverizes the surface of at least 11 other moons of Saturn of particles of ice. What explains that these bodies are among the most brilliant of the Solar system, Enceladus, is the most thoughtful body of our system with an  albedo We call up albedo of a body, the report enters the quantity of light which it reflects or diffuses and the quantity of light which it receives. As comparison the albedo of the basalt is of 0,05 that of the lime is of 0,36 that of the chalk 0,85. The basalt reflects that 5 % of the successful light. The maximal reflectivity being 1. close to 1. " Enceladus modifies constantly the surface of the other worlds which revolve in the whirlwind of particles of ice that she generates ", asserts Anne Verbiscer, a scientist of the department of astronomy at the university of Virginia and a main author of the study appeared in Science on February 9th, 2007. " We nicknamed Enceladus ' artist in graffiti ' because of its capacity to modify the appearance of the other moons.

The ring of particles which forms Enceladus around Saturn is called ring E. At least 11 other moons revolve on this ring and are constantly bombarded by the ice-cold particles emitted by Enceladus.

Enceladus has, in spite of its small size (500 kilometers in diameter) a geologic activity. Almost seven times as small as our Moon, Enceladus knows perpetual modifications of its surface due to its geysers which spread of the ice and some liquid water, the likely consequences of the conditions of heat and pressure of its depths. The absence of crater in plains shows that some of these regions are old of less than 100 million years. Enceladus presents smoother zones of plains, events of ice, fish bones and long lines of fracture in its South Pole. These cracks are the source of the panache of ice which splash its orbit, and which accumulate on its trajectory. Geysers, situated in the South Pole of Enceladus,

explode constantly, by ejecting particles of ice and by spreading a slender swirling trail in the trail of the moon, which eventually constitutes the ring of particles of ice which we know. This one is supplied in every orbit of the moon around its planet. These particles can so collide with one of the moons enclosed in the ring E, including Enceladus itself when it crosses its own emissions. Anne Verbiscer: "we wondered why the other moons close to the ring E were so brilliant, although they are not geologically active as Enceladus. The answer, we know it henceforth, is that these other moons are riddled so to speak by the particles of ice ejected by Enceladus".

Source : Cassini