Saturn's moon Enceladus, according to the latest data of the American spacecraft "Cassini", has an unusual train, which is now studied by experts of the planetary community. Semi-transparent "gauze" this train is formed mysterious jets erupting from the surface of the satellite. And their composition was multicomponent and very unusual.

Before space missions about Enceladus there was very little information. Mostly about the body, scientists told a probe "Cassini", although he was found quite a long time. Opening of Enceladus belongs to William Herschel, who discovered the satellite in 1789. Later it became known that Enceladus does orbital motion in the medium dense enough the E ring of Saturn, and apparently can share substance.

Himself Enceladus small, its diameter is about 500 km and the icy surface of the satellite, well reflects the sunlight. The first two interplanetary probe Voyager" and "Voyager-2" have passed by Enceladus at the beginning of 1980-s, and since then it nebesnoe body is of great interest to researchers. Pictures from the Voyager" found details of the relief of Enceladus - it turns out that there are craters and plains.

Since 2005 space mission "Cassini" started much more detailed investigation of unusual companion. The photos were discovered gigantic jets erupting from the South pole of Enceladus, a whole train of water, esterhuyse the result of some dynamic processes under the icy crust of Enceladus. It is believed that the causes of this gown is not only tectonic when there are faults and movements of the crust of the satellite, but also the internal heating, which creates the processes of the type of volcanic and tidal waves.

While scientists believe that it is possible replenishment saturninag the E ring water mass, thrown in eruptions from the surface of Enceladus. Moreover, analyzed the composition of the train was so heterogeneous that it share it to a qualitatively dissimilar plasma-dust formation. They are spawned "plasma lab" turbulent, satellite sending a geyser jets for hundreds of kilometres away from the ice surface, under which, as was raging ocean. And he manifests itself only through these water eruptions.

Scientists believe that the jets in the photo "Cassini visible plumes with "dusty plasmas" - a state which is theoretically possible, but not previously described in the observations of Enceladus. The obtained results are discussed in two articles published in the Journal of Geophysical Research-Space Physics.

In the Universe, believed to 99 percent of matter is in the form of plasma. The mission "Cassini" is used to directly observe the behavior of clouds ions and electrons in the vicinity of Enceladus, in his "veil". Scientists want to understand how the Sun provides energy plasma environment of Saturn and as charged plasma in a magnetic field gas giant (because it determines weather" in his powerful atmosphere).

Icy and stormy Enceladus is the main source of ionized material which led to huge (compared to earth!) the magnetosphere around Saturn. Hundredweight of water vapor per second (which is a lot one small comets) comes from a long cracks so-called tiger strips in the South polar area. The release is converted to a trail of icy particles and neutral gas, mainly water vapor. And gets charged particles this "veil" when interacting with plasma held by the magnetosphere of Saturn.

The composition of this unique gas-dust-plasma mixtures was investigated in the mission "Cassini" by several instruments, including spectrometer and magnetometer tools for visualization of the magnetosphere and devices for reception of electromagnetic and plasma waves. Most interesting was that the particle sizes range from small clusters of water (about several molecules) to 100 microns. They capture electrons, buying their charge. Up to 90 percent of electrons plume captured a large heavy particles.

"The Cassini" watched in these conditions positively charged ions can be small, "easy" varieties of plasma, and negatively charged particles turn into "heavy" plasma components. This process spawns "abnormal" plasma radically different from those that form the "normal" plasma, in which the free electrons in a thousand times easier than massive positive ions.

In the article "Dusty plasmas in the vicinity of Enceladus" group of Swedish and American scientists analyzes the monitoring of the radio and plasma wave, received in 2008 in four aerial reconnaissance satellite. The probe found a high plasma density (as of ions and electrons) within the plume of Enceladus, which is somewhat strange - electron density, as a rule, is lower than that of ions. The researchers suggest that dust particles in the size from 1 nm to 1 micron "swept" negatively-charged electrons.

The mass of these nanoscale particles varies from several hundred to several tens of thousands of atomic mass units (protons), i.e. they contain tens of thousands of interconnected water molecules. About half of negatively charged electrons attached to these particles and their interaction with the positively charged components leads to inhibition of the latter. Since dust is charged and behaves as part of the plasma cloud, the authors believe this state of substances other than dust that just gets in the plasma.

"So strong is the link points to a possible state of the so-called dusty plasma, not dust plasma, which is widely found in interplanetary space, " says the study's lead author Michiko Morooka from the Swedish Institute of space physics. - Dust plasma hitherto observed directly only in the upper atmosphere of the Earth".

Interestingly, the behavior of dust subordinated to the General behavior of the plasma. This increases the complexity of the system, changes its properties and can lead to completely new interactions. It is known that dusty plasmas exists in the tails of comets and dust rings around the Sun, but scientists rarely get the chance to analyze it in direct spans such entities to directly measure their performance.

Another analysis based on data of plasma spectrometer "Cassini", showed the presence of nanoparticles with electrical charge equal to the charge excess of one electron. "Plasma spectrometer ship has allowed us to discover and analyze new classes of charged particles, whose existence nobody even suspected in those years when he developed this tool" - said the study's lead author Tom hill from rice University (USA).

It should be noted that the characteristics of the plume of Enceladus was identified by combining the results of all the tools mission "Cassini", which is in the orbit of Saturn started since 2004. After the initial discovery by train magnetometer measurements Sven Simon from Cologne University and Hendrik Kigelia from Braunschweig University (University, Germany) showed that the observed perturbations of Saturn's magnetic field due to the negatively charged dust particles in the plume.

These results are published in 2011 in the Journal of Geophysical Research, Space Physics. Previous data obtained ion and neutral mass spectrometer showed the complex composition of the gas in the train, and the cosmic dust analyzer were found sodium salt particles in the plume of Enceladus. This situation can occur only when the train emerges from a liquid salt water.

So, on Enceladus there is the ocean is salty as the ocean of the Earth, but covered with ice shell. Breaks the ice crust gushing geysers, form plumes of satellite and create interaction of the satellite with the E ring, in which he dwells. The study of the plasma environment surrounded by Enceladus allows to speak about its unique features not previously found to researchers.