26 January 2011: For many years was have researchers debate whether Enceladus, a small moon outside the rings of Saturn, floating is home to a huge subterranean Ocean. Is es-- or not wet? New evidence is now, tilt the scales. Not only do Enceladus probably have an ocean, it is likely this ocean fizzy like a drink and friendly to micro-organisms are could.
The story begins in the year 2005 when NASA flew past Enceladus for a close encounter probe Cassini.
"Geophysicists expected this small world, a chunk of ice, cold, dead and uninteresting, be", says Dennis Matson of the Jet Propulsion Laboratory of NASA. "Boy, were we surprised!"
Cassini found the small moon busily puffing plumes of water vapor, icy particles and organic compounds from cracks in its frozen carapace (now known as "tiger stripes"). Mimas, the same size, as researchers expected a nearby Moon was about as dead, but Enceladus was precociously active.
Many researchers considered the icy jets as evidence of a large underground body of water. Near the surface, pockets of liquid water at a temperature in the vicinity of 32o f could explain the watery plumes. But there were problems with this theory. For one thing, where was the salt?
In the first mercury, Cassini's instruments carbon, hydrogen, oxygen, nitrogen, and various hydrocarbons in the plume discovered gases. But there was no element of salt, that will contain sea water.
In 2009, the missing salt - in a surprising place is Cassini's cosmic dust Analyzer.
"It was not in the plume gases, where we had been looking for for you," says Matson. "Instead, sodium and potassium salts and carbonates were in the plume of icy particles. * locked up and the source of these substances must be an ocean." "Stuff dissolved in an ocean these grains is similar to the content."
The latest Cassini observations presented another interesting discovery: thermal measurements revealed cracks with temperatures - 1200 F (190 degrees Kelvin).
"This discovery sets our watches!" says Matson. "Temperatures have high volcanic be." "Heat of the underground ice, must create from the inside, enough, to some a underground waterworks melting will flow."
The finding led the scientists to consider how an ocean limited content by a single ice as much as tens of kilometres thick could reach the surface.
"You have been sprayed ever have when you popped up in the soda can?" asks Matson.
He and his colleagues suggest model suggests that gases in water dissolved deep below the surface form bubbles. Because the density of the resulting 'sparkling waters"is less than that of the ice, the liquid quickly rises up through the ice on the surface *.
"Most of the water spreads laterally and 'warm' a thin surface ice cover, which is about 300 metres thick," explains Matson. "But some collecting it builds pressure in the underground chambers, and then blasts from spew through small holes in the ground, such as soda, you can be open." "During the remaining water cooling, seeps down to complement it, the ocean and the start over and over again."
Another mystery remains: "Where the heat comes from on this tiny body?" asks himself, Larry Esposito of the University of Colorado. "We think, heating help tide could."
Saturn powerful tides cause actually easily change the shape of Enceladus as it orbits. Flexendes movements in the Interior of the Moon produce heat-such as the heat that you feel in a paper clip, if you fast to and turn. In this model powers internal friction volcanic activity that warms and the ice melts.
"It is clear now, that, what produced requirements whatever the heat, Enceladus many for life," says Esposito. "We know that it has a liquid Ocean, Organics and an energy source." "And, we know of organisms on Earth in similar environments."
Nobody white sure, what is under the ice in front of him, but it seems this small moon has a story to tell: erupting jets, a subterranean Ocean, the possibility for life.
And they thought that this place was boring.
Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA
The Cassini-Huygens mission is a joint project of NASA, ESA and the Italian Space Agency. JPL, a division of the California Institute of technology in Pasadena, California, manages mission to NASA's Science Mission Directorate, Washington, D.C.
* Cassini cosmic dust Analyzer principal investigator Ralf Srama of the Max Planck Institute for nuclear physics in Heidelberg, Germany, led the study.
* In their 1988 study on Europe led Crawford and Stevenson the term "Perrier Ocean" for this model. See G. D. Crawford, D. j. Stevenson, Icarus, 73, 66-79 (1988).
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