Posted on 11/23/2009 3:52:25 PM PST by Daffynition
Nice! You can see which towns have a Firday Night Football game! /s
Cool photos. Figured it must be a moon of some sort - found this on a search to fill in the blanks for me (and probably others):
Enceladus is the sixth-largest moon of Saturn.[14] It was discovered in 1789 by William Herschel.[15] Until the two Voyager spacecraft passed near it in the early 1980s, very little was known about this small moon besides the identification of water ice on its surface.
The Voyagers showed that the diameter of Enceladus is only 500 km, about a tenth of that of Saturn’s largest moon, Titan, and reflects almost 100% of the sunlight that strikes it. Voyager 1 found that Enceladus orbited in the densest part of Saturn’s diffuse E ring, indicating a possible association between the two, while Voyager 2 revealed that despite the moon’s small size, it had a wide range of terrains ranging from old, heavily cratered surfaces to young, tectonically deformed terrain, with some regions with surface ages as young as 100 million years old.
In 2005, the Cassini spacecraft began to acquire additional data on Enceladus, answering a number of the mysteries opened by the Voyager spacecraft and starting a few new ones. Cassini performed several close flybys of Enceladus, revealing the moon’s surface and environment in greater detail. In particular, the probe discovered a water-rich plume venting from the moon’s south polar region. This discovery, along with the presence of escaping internal heat and very few (if any) impact craters in the south polar region, shows that Enceladus is geologically active today.
Moons in the extensive satellite systems of gas giants often become trapped in orbital resonances that lead to forced libration or orbital eccentricity; proximity to the planet can then lead to tidal heating of the satellite’s interior, offering a possible explanation for the activity.
Enceladus is one of only three outer solar system bodies (along with Jupiter’s moon Io and Neptune’s moon Triton) where active eruptions have been observed. Analysis of the outgassing suggests that it originates from a body of sub-surface liquid water, which along with the unique chemistry found in the plume, has fueled speculations that Enceladus may be important in the study of astrobiology.[16] The discovery of the plume has added further weight to the argument that material released from Enceladus is the source of the E ring.
More astrobiology and Mandelbulbs: The Unravelling of the Real 3D Mandelbulb
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Outstanding.
Thanks for posting. We need threads like this for a much needed break.
You may have Enceladus and Triton but Io is mine.
Now that’s cool...
Definitely.
The top image of Enceladus is also today’s Astronomy Picture of the Day.
In the animation, is the edge of the dark(er) area that progresses downward the terminator?
Absolutely right! What especially threw me off were the names left to right, they trace out Alexandria, Cairo, Baghdad, and, at the extreme right edge, Damascus . With all the tension in the ME, I was prepared for the worst ;-)
Thank you for posting the details.
WOW! Spectacular! What an awesome solar system we live in!
I’m not sure, but I think that’s twilight from the sunlight diffusing off the gas being spewed. The terminator is at the horizon. Someone correct me if I’m wrong.
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