30 Jul 2012
A giant landslide on Iapetus stretches halfway across a 75-mile (120 km) crater. CREDIT: NASA/JPL/Space Science Institute

Scientists are hoping that long landslides visible on Saturn's moon Iapetus may provide clues to understand similar movements here on Earth, in particular how earthquake fault lines often slip farther than expected.  Scientists have concluded that flash heating could cause the falling ice to move 10 to 15 times farther than expected.

You can find similar extended landslides here on Earth and even mars but they are usually made of rock.  It is believed there is a link between the debris both rock and ice on all three locations.

Lead scientist of Washington University, Kelsi Singer stated,  "We think there's more likely a common mechanism for all of this, and we want to be able to explain all of the observations."

Hard Ice

These landslides stretch as far as 50 miles or 80 kilometers on the surface of Iapetus.  Singer's team used images from NASA's Cassini spacecraft to identify 30 different displacements.

What makes Iapetus so unique is that unlike many other bodies in the solar system, Iapetus is composed of almost entirely frozen water, with little bits of rock and carbonaceous material that make half the moon appear darker than the other on the surface though. 

In addition, Iapetus has a mountainous ridge that bulges out at its equator, making it one of the oddest formations in the solar system, due to its shape and height.

Since temperatures get down to -300 degrees Farenheit (-150 degrees Celsius) the ice is different than ice on Earth, as its very hard and dry.  This makes it more comparable to rock like material.  Because slow-moving ice should create a lot of friction and travel slower, but it was not the case on Iapetus.  Scientists concluded that flash heating may be giving the material the extra speed on Iapetus.

Flash Heating Speed and Distance

Flash heating is the result of materials falling so fast the heat doesn't have time to dissipate.  Rather, it stays concentrated in small areas, reducing friction and allowing them to travel faster and farther.

Scientists believe the landslides are recent in relative terms and may have been triggered by impacts in the last billion years or so.

The Ice and Rock Connection

You would think that differences in gravity, atmosphere and water would make landslides that are on Iapetus difficult to reproduce in the laboratory.  Since they happen on different worlds makes it more likely the mechanism which triggers the slide is dependent on things unique to either location.

"We have them on Iapetus, Earth and Mars.  Theoretically, they should be very similar," according to Singer.

There is an implication of friction at fault lines which makes earthquakes.  Sometimes a fault will slide farther than scientists can explain based on friction alone.  If there were flash heating involved, it would explain why things often occur as they do, resulting in a better understanding of earthquakes.

Source: Space.com


Use this QR code in a QR reader application on mobile to open quickly on a mobile device

blog comments powered by Disqus

Flight-Stew Now Live

Be sure to visit our newest site, Flight-Stew, now active!

Recently Added

Subscribe

Poll

Do you prefer 3D stereoscopic gaming over standard?


Show Results

[forcestyle][nozoom][nocaption]

Donate

       Support Tech-Stew
   [nozoom]
        Make a Donation

Recent Comments