Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




SATURN DAILY
Enceladus rains water onto Saturn
by Staff Writers
Paris (ESA) Jul 27, 2011


This image of Enceladus was taken by Cassini on 25 December 2009. See a detailed chart and caption of the Herschel observations here.

ESA's Herschel space observatory has shown that water expelled from the moon Enceladus forms a giant torus of water vapour around Saturn. The discovery solves a 14-year mystery by identifying the source of the water in Saturn's upper atmosphere.

Herschel's latest results mean that Enceladus is the only moon in the Solar System known to influence the chemical composition of its parent planet. Enceladus expels around 250 kg of water vapour every second, through a collection of jets from the south polar region known as the Tiger Stripes because of their distinctive surface markings.

These crucial observations reveal that the water creates a doughnut-shaped torus of vapour surrounding the ringed planet.

The total width of the torus is more than 10 times the radius of Saturn, yet it is only about one Saturn radius thick. Enceladus orbits the planet at a distance of about four Saturn radii, replenishing the torus with its jets of water.

Despite its enormous size, it has escaped detection until now because water vapour is transparent to visible light but not at the infrared wavelengths Herschel was designed to see.

Saturn's atmosphere is known to contain traces of gaseous water in its deeper layers. A particular enigma has been the presence of water in its upper atmosphere.

First reported in 1997 by teams using ESA's Infrared Space Observatory, the source of this water was unknown until now. Computer models of these latest Herschel observations show that about 3-5% of the water expelled by Enceladus ends up falling into Saturn.

"There is no analogy to this behaviour on Earth," says Paul Hartogh, Max-Planck-Institut fur Sonnensystemforschung, Katlenburg-Lindau, Germany, who led the collaboration on the analysis of these results.

"No significant quantities of water enter our atmosphere from space. This is unique to Saturn."

Although most of the water from Enceladus is lost into space, freezes on the rings or perhaps falls onto Saturn's other moons, the small fraction that does fall into the planet is sufficient to explain the water observed in its upper atmosphere.

It is also responsible for the production of additional oxygen-bearing compounds, such as carbon dioxide.

Ultimately, water in Saturn's upper atmosphere is transported to lower levels, where it will condense but the amounts are so tiny that the resulting clouds are not observable.

"Herschel has proved its worth again. These are observations that only Herschel can make," says Goran Pilbratt, ESA Herschel Project Scientist.

"ESA's Infrared Space Observatory found the water vapour in Saturn's atmosphere. Then NASA/ESA's Cassini/Huygens mission found the jets of Enceladus. Now Herschel has shown how to fit all these observations together."

.


Related Links
Herschel at ESA
Explore The Ring World of Saturn and her moons
Jupiter and its Moons
The million outer planets of a star called Sol
News Flash at Mercury






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





SATURN DAILY
Tempest-from-hell seen on Saturn
Paris (AFP) July 6, 2011
Imagine being caught in a thunderstorm as wide as the Earth with discharges of lightning 10,000 times more powerful than normal, flashing 10 times per second at its peak. Now imagine that this storm is still unfolding, eight months later. One of the most violent weather events in the Solar System began to erupt on Saturn last December and is still enthralling astronomers, the British jou ... read more


SATURN DAILY
Unique volcanic complex discovered on Lunar far side

Moon Express Announces Dr. Alan Stern as Chief Scientist

Northrop Grumman Honored by IEEE for Development of Lunar Module

Two NASA Probes Tackle New Mission: Studying The Moon

SATURN DAILY
NASA's Next Mars Rover to Land at Gale Crater

Opportunity Closing In On Spirit Point At Endeavour Crater

MAVEN Mission Completes Major Milestone

NASA says Mars mountain will read like 'a great novel'

SATURN DAILY
SwRI suborbital astronaut payload specialists move to flight planning phase, release mission patch

Graybiel Lab poised for next chapter of space exploration

Space Program Mavens Comment on the Future of Space Exploration

This Time It's Both Rocket Science AND Surgery

SATURN DAILY
Spotlight Time for Tiangong

China launches new data relay satellite

Time Enough for Tiangong

China launches experimental satellite

SATURN DAILY
ISS to be sunk after 2020: Russian space agency

Certification for ISS onboard astronaut

NASA and International Partners Discuss New Uses for Space Station

NASA, SpaceX agree on space station flight

SATURN DAILY
Russia sends observation satellite into space

NASA inks agreement with maker of Atlas V rocket

Russia launches 2 foreign satellites into orbit

ILS Proton Successfully Launches the SES-3 Satellite for SES

SATURN DAILY
Distant planet aurorae modeled

Exoplanet Aurora: An Out-of-this-World Sight

Ten new distant planets detected

Microlensing Finds a Rocky Planet

SATURN DAILY
Turksat turns to GMV for control of its satellites

Lockheed Martin's Multi-Mission Signal Processor Completes Tracking Test

Sharper deeper faster 3D imaging

Rare Coupling of Magnetic and Electric Properties in a Single Material




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement