Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cassini finds recent, unusual geology on Enceladus

27.07.2005


New detailed images taken by NASA’s Cassini spacecraft of the south polar region of Saturn’s moon Enceladus reveal distinctive geological features, and the most youthful terrains of any seen on Enceladus. These findings point to a very complex evolutionary history for Saturn’s brightest, whitest world.



Cassini’s flyby on July 14 brought it within 175 kilometers (109 miles) of the surface of the icy moon. The close encounter revealed a landscape near the south pole littered with house-sized ice boulders, carved by tectonic patterns unique to Enceladus, and almost entirely free of impact craters. These features set the southerly region apart from the rest of the moon.

The new image products can be seen at http://ciclops.org, http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.


As white as fresh snow, Enceladus (505 kilometers, 314 miles across) has the most reflective surface in the solar system. Previous Cassini flybys have revealed that Enceladus, in contrast to the other icy moons of Saturn, possesses lightly cratered regions, fractured plains and wrinkled terrain.

The new findings add to the story of a body that has undergone multiple episodes of geologic activity spanning a considerable fraction of its lifetime, and whose southern-most latitudes have likely seen the most recent activity of all. These same latitudes may also bear the scars of a shift in the moon’s rate of spin. This speculation which, if true, may help scientists understand why Enceladus has a tortured looking surface, with pervasive crisscrossing faults, folds and ridges.

The most remarkable images show ice blocks, about 10 to 100 meters (33 to 328 feet) across, lying in a region that is unusual in its lack of the very fine-grained frost that seems to cover the rest of Enceladus.

"A landscape littered with building-sized blocks was not expected," said Dr. Peter Thomas, an imaging team member from Cornell University, Ithaca, N.Y. "The minimal cover of finer material and the preservation of small, crossing fracture patterns in the surrounding areas indicate that this region is young compared to the rest of Enceladus."

False color composites of this region, created from the most recent images, show the largest exposures of coarse-grained ice fractures seen anywhere on the satellite. It also supports the notion of a young surface at southern latitudes.

"These southern exposures of coarse-grained ice are aligned with tectonic "stripes" and not covered by the fine-grained materials that one would expect from various space weathering processes," said Dr. Alfred McEwen, an Imaging Team member at the University of Arizona, Tucson.

The apparent absence of sizable impact craters also suggests that the south pole is younger than other terrains on Enceladus. These indications of youth are of great interest to scientists who have long suspected Enceladus as one possible source of material for Saturn’s extensive and diffuse E ring, which coincides with the icy moon’s orbit. Young surfaces represent a challenge as it has generally been believed that Enceladus is too small and too cold to generate the heat required to modify its surface.

Some of the latest images, which have revealed additional examples of a distinctive "Y-shaped" tectonic feature on Enceladus in which parallel ridges and valleys appear to systematically fold and deform around the south polar terrains, may hint at the answer.

"These tectonic features define a boundary that isolates the young, south polar terrains from older terrains on Enceladus," noted Dr. Paul Helfenstein, an associate of the Imaging Team also at Cornell University. "Their placement and orientation may tell us a very interesting story about the way the rotation of Enceladus has evolved over time and what might have provided the energy to power the geologic activity that has wracked this moon."

Cassini will explore Enceladus further in a future close flyby planned for March 2008.

Preston Dyches | EurekAlert!
Further information:
http://www.nasa.gov

More articles from Physics and Astronomy:

nachricht UNH scientists help provide first-ever views of elusive energy explosion
16.11.2018 | University of New Hampshire

nachricht NASA keeps watch over space explosions
16.11.2018 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>