Aurora of moon of Saturn 'Circuit'

April 21, 2011 last updated at 14: 52 GMT Aurora differ widely in intensity and they are generally weaker by the Jupiter-Saturn is a flickering "northern lights" phenomenon thanks to a flow of electrons to and from his Moon of Enceladus, researchers say.

A report in nature suggests this Aurora would be weak, and in the ultraviolet part of the light spectrum.

The electrical "circuit" between Jupiter and three of its moons is similar to search by the Cassini probe.

Electrons flow from Enceladus Poland in a large loop and Aurora result and where they hit Saturn's magnetic field.

The Aurora process is similar to what is happening in high latitudes of the Earth; Here are the paths of the fast-moving charged particles from the solar wind magnetic field of the Earth curved and emit the shows we know as the northern and southern lights.

On the other hand the fields cover created by Jupiter and Saturn moons of, and what is known conclusion what brings is particles directly from the satellite, an electrical circuit as electrodynamic coupling in fact.

The mechanism behind Jupiter's Aurora is believed that its sulphur content of its Moon of IO's volcanic activity, divided by the sunlight into electrons and ions.

On Saturn's moon of Enceladus, however is the suspected source of the electrons "Cryovolcanism" - volcanic activity, the above liquids or at Enceladus, salty ice shoots.

'Rare opportunity' last year, the Cassini mission was extended to 2017

The spacecraft Cassini studied Saturn and its moons since it came in 2004 having made 12 close passes of Enceladus.

The close encounter, which on 11 August 2008 occurred on, scientists discovered a large stream of ions (molecules with electrons removed) of Moon and then confirms the electron loops.

"I think it is a very interesting discovery, very exciting," said Andrew Coates, co-author of the paper of the University College London.

"Five or six years, we did not know that Enceladus was material in the solar system - plaster, now we exciting effects, such as the magnetic and electrical current links in the ionosphere of Saturn produced this (Aurora) in place," he told BBC News.

The team says, that the Aurora about one-tenth the intensity of those on Jupiter seen, and that in intensity - by as much as three times vary.

The they of date, is down to the variations in the output of the geysers which are feeding the process - a process, says Professor Coates seems likely to happen somewhere else.

"It is likely a universal process;" It could be something that happens in other places like [Neptune's moon] Triton or extrasolar planets where it 'hot Jupiter'. "

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Comet gives Saturn ring waves

March 31, 2011 last updated at 19:14 pm by Neil Bowdler science reporter, BBC News as a comet produces impact waves in a planet rings of TimeScientists say, the strange waves observed in the ring of Saturn and Jupiter have been caused by comets.

The waves, which the researchers say the waves are similar to corrugated iron, were both discovered the rings of Saturn and Jupiter's lesser-known rings.

The waves in Jupiter's rings are believed to by Comet Shoemaker-Levy 9, which struck the planet 1994 caused be. Information is published in two separate papers in the journal Science.

The researchers analysed images of Jupiter's rings taken from the Galileo spacecraft in 1996 and 2000 and the new horizons probe in 2007. You have us with images of Saturn's rings, by the spacecraft Cassini during 2009.

What they found were waves, which compare the researchers on the corrugated Tin Roof, which, when lit from a low angle, as alternating dark and light bands.

This wave formation was extends, ring of Saturn's entire C for thousands of miles found. It seemed watched part of a similar pattern earlier in the weaker D ring. Now, at least two separate spirals discovered Jupiter's rings.

They researchers believe that by dirt, most likely from a Comet, impact on the rings, and flip they were caused.

"The material passes through the ring and basically means that the entire ring to easily with respect to the planet equatorial plane be inclined, and then distorted it form spiral from this pattern," said Dr. Matthew Hedman at Cornell University in New York.

In the course of time, the cardboard was more tightly wound spiral, during the heavy planet rings again pulled into alignment. However, complete this process appreciate decades could take the researchers.

The team was then able, the rewind process using mathematical models to an estimated time of impact. For Saturn they 1983 at a point arrived, but still no possible candidate Comet have found.

With Jupiter, she discovered at least two spirals and so maybe two impact events. If they back them a the process for one of the spirals reached wound, the point in the year 1994, in the same year of the Shoemaker-Levy 9 impact.

Dr. Mark r. Showalter of SETI Institute in California, recalls the moment he and Dr. Hedman the importance of the date.

"" Matt and I were talking, say now wait a second date sounds a little something familiar and frankly we had to run on Wikipedia way to questions, "when Shoemaker-Levy 9 hit Jupiter?"and was the eureka moment when we had realized we a smoking gun "he told the BBC."

The second spiral led to an estimated impact event were caused in 1990, which the scientists can hypothesise by deposits from a previous close encounter with Shoemaker-Levy 9.

Images that also proposed more impact on Jupiter's rings could be occurred spacecraft of the new horizons in September 2001 and December 2003, but additional recognizers be necessary, confirm these results.

Leave an a scar of Shoemaker-Levy 9 impact with Jupiter

Dr. Showalter said waves like the studied in that new documents could give clues as to the frequency of such events of the outer solar system.

"Rings are Comet catcher", he says. "We probably already realized that comets make rings on a regular basis but we never realized before that everyone puts comets own signature in rings if it goes through and that the story in this spiral is recorded the pattern."

"Decades later, you can actually consider same ring, find this ripple pattern, and each of them then you know something about what the ring hit and when it did so."

The work, Professor Alan Fitzsimmons, Comet researcher at Queen's University of Belfast, commented: "the papers show exactly what you can do, if you work this beautiful space ship have observation of outer planets close up."

He said the gravitational forces of the giant planets were enough to tear apart fragile comets, create fields of garbage which seen causing the effects in ring systems.

Asteroid could be torn to, he said, but this was apart by tidal forces so-called rather at the Jupiter, close to the asteroid belt are seen.

He said the work would researchers the possibility to give to "how many times directly calculate objects the giant planets, we have fought to tie beat."

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