On Mimas, the moon of Saturn, there may be an icy ocean

In the 18th century, astronomer William Herschel discovered the smallest eighth satellite of Saturn, which had not been seen before. Mimas was named after the son of Gaia, the goddess of Greek myths. The satellite’s diameter is about 400 kilometers, and its surface is “decorated” with a huge 130-kilometer crater.

NASA experts found that Mimas in orbit behaves differently than most other satellites. The fact is that, moving in its orbit around Saturn, Mimas makes slow oscillations. Scientists believe that the reason for these swaying may be the presence in the depths of a large amount of water, of course, in liquid form.

The photographs of Mimas were transmitted to the earth by the interplanetary station Cassini, which has been in the orbit of Saturn for 10 years, studying this gas giant and its surroundings. Cassini Project Manager Radwan Tadjeddin reported on the high amplitude of the satellite’s vibrations while traveling in orbit. To be more precise, these fluctuations are actually twice as large as expected in the calculations.

Libration, the slow rocking of a satellite, is already a familiar phenomenon for astronomers. Observation revealed it in some satellites of other planets. The cause of libration can be either the presence of liquid water in large quantities, or the shape of the satellite is the reason for this behavior.



In the process of studying the data, scientists created several models of Mimas’s “behavior”, some of which were created according to the data provided by Cassini. There are two main versions of the liberation of Mimas. According to the first, the ocean is located at a depth of 24 to 31 kilometers from the surface. And tidal heating contributes to satellite vibrations. According to the second theory, libration is caused by the unusual shape of the Mimas core. It is assumed that the core may have an oval shape.

However, both theories have contradictions that are difficult to deny. If an ocean existed inside Mimas, then faults would be discovered on the surface of the satellite through which spills of liquid water would occur from time to time. But nothing of the kind has yet been observed. In order to confirm or refute the second theory, we need more data, which, unfortunately, is not yet available.
If the presence of liquid water beneath the icy surface of Mimas is proved, then astronomers are likely to have another potentially inhabited world. An expedition to Europe is already planned (unmanned, by itself). Maybe Mimas will interest scientists so much that it will be decided to send the station there too.

Via popularmechanics