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Titan Cryovolcano
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The Cassini probe has spotted a 1,500m-high mountain with a deep pit in it, and what looks like a flow of material on the surrounding surface.
The new feature, which has been dubbed "The Rose", was seen with the probe's radar and infrared instruments.
Titan has long been speculated to have cryovolcanoes but its hazy atmosphere makes all observations very difficult.

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RE: Titan Hot Spot
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Cassini Spots Potential Ice Volcano on Saturn Moon

NASA's Cassini spacecraft has found possible ice volcanoes on Saturn's moon Titan that are similar in shape to those on Earth that spew molten rock.
Topography and surface composition data have enabled scientists to make the best case yet in the outer solar system for an Earth-like volcano landform that erupts in ice. The results were presented today at the American Geophysical Union meeting in San Francisco.



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Cryovolcanism
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 Data collected during several recent flybys of Titan by NASA's Cassini spacecraft have put another arrow in the quiver of scientists who think the Saturnian moon contains active cryovolcanoes spewing a super-chilled liquid into its atmosphere. The information was released today during a meeting of the American Geophysical Union in San Francisco, Calif.

"Cryovolcanoes are some of the most intriguing features in the solar system. To put them in perspective -- if Mount Vesuvius had been a cryovolcano, its lava would have frozen the residents of Pompeii" - Rosaly Lopes, a Cassini radar team investigation scientist from NASA's Jet Propulsion Laboratory in Pasadena, Calif.

Rather than erupting molten rock, it is theorised that the cryovolcanoes of Titan would erupt volatiles such as water, ammonia and methane. Scientists have suspected cryovolcanoes might inhabit Titan, and the Cassini mission has collected data on several previous passes of the moon that suggest their existence. Imagery of the moon has included a suspect haze hovering over flow-like surface formations. Scientists point to these as signs of cryovolcanism there.

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Titan Active volcano
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See also this thread

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The brightest spot on Saturn's moon Titan has been seen brightening and growing, suggesting it might be an active volcano, a controversial analysis of images from the Cassini spacecraft suggests. If so, it would be the first indication of current volcanic activity on the giant moon.
Scientists are interested in whether Titan is volcanically active because volcanoes could help supply the large amount of methane seen in its atmosphere. The methane is quickly broken down by sunlight, so it must be getting replenished somehow.

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RE: Titan bright Spot
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According to University of Arizona scientists and Cassini team members a 300-mile-wide patch that outshines everything else on Titan at long infrared wavelengths appears not to be a mountain, a cloud or a geologically active hot spot.

"We must be looking at a difference in surface composition. That's exciting because this is the first evidence that says not all of the bright areas on Titan are the same. Now we have to figure out what those differences are, what might have caused them" - Jason W. Barnes, postdoctoral researcher at UA's Lunar and Planetary Lab.

When NASA's Cassini spacecraft flew by Titan on March 31 and again on April 16, its visual and infrared mapping spectrometer saw a feature that was spectacularly bright at 5-micron wavelengths just southeast of the continent-sized region called Xanadu.

The bright spot occurs where Cassini's visible-wavelength imaging cameras photographed a bright arc-shaped feature approximately the same size in December 2004 and February 2005.


Combined VIMS and ISS images of Titan's mysterious bright red spot .(Credit: NASA/JPL/University of Arizona/Space Science Institute)


Cassini's radar instrument, operating in the "passive" mode that is sensitive to microwaves emitted from a planetary surface, saw no temperature difference between the bright spot and surrounding region. That rules out the possibility that the 5-micron bright spot is a hot spot, such as a geologically active ice volcano.

Cassini microwave radiometry also failed to detect a temperature drop that would show up if some two-mile high mountain rose from Titan's surface.

And if the 5-micron bright spot is a cloud, it's a cloud that hasn't moved or changed shape for three years, according to ground-based observations made at the Keck Telescope and with Cassini's visual and infrared mapping spectrometer during five different flybys.

"If this is a cloud, it would have to be a persistent ground fog, like San Francisco on steroids, always foggy, all the time. The bright spot must be a patch of surface with a composition different from anything we've seen yet. Titan's surface is primarily composed of ice. It could be that something is contaminating the ice here, but what this might be is not clear. There's a lot left to explore about Titan. It's a very complex, exciting place. It's not obvious how it works. It's going to be a lot of fun over the next couple of years figuring out how Titan works" - Jason W. Barnes.

Barnes and 34 other scientists report the research in the October 7 issue of Science.

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RE: Titan Hot Spot
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The "hot spot" theory has been more or less abandoned.
Radar observations have already confirmed that the spot isn't glowing or emitting energy on it's own.
The scientists still don't know what it is though.


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RE: Titan Red Spot
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The visual and infrared mapping spectrometer instrument onboard Cassini has found an unusual bright, red spot on Titan.
This dramatic colour (but not true colour) image was taken during the April 16, 2005, encounter with Titan. North is to the right. In the centre it shows the dark lanes of the "H"-shaped feature discovered from Earth and first seen by Cassini last July shortly after it arrived in the Saturn system. At the south-western edge of the "H" feature, near Titan's limb (edge), is an area roughly 500 kilometres across. That area is 50 percent brighter, when viewed using light with a wavelength of 5 microns, than the bright continent-sized area known as Xanadu .Xanadu extends to the northwest of the bright spot, beyond the limb (edge) of Titan in this image. Near the terminator (the line between day and night) at the bottom of this image is the 80 kilometre crater that has been previously seen by the Cassini radar, imaging cameras, and the visual and infrared spectrometer .
At wavelengths shorter than 5 microns, the spot is not unusually bright. The strange spectral character of this enigmatic feature has left the team with four possibilities for its source: the spot could be a surface coloration, a mountain range, a cloud, or a hot spot.


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The hot spot hypothesis will be tested during a Titan flyby on July 2, 2006, when the visual and infrared spectrometer will take night time images of this area. If it is hot, it will glow at night.
This colour image was created from separate images in the 1.7 micron (blue), 2.0 micron (green), and 5.0 micron (red) spectral windows through which it is possible to see Titan's surface. The yellow that humans see has a wavelength of about 0.5 microns, so the colours shown are between 3 and 10 times more red than the human eye can detect.




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Titan Hot Spot
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Saturn's moon Titan shows an unusual bright spot that has scientists puzzling over what it might be.

The recently discovered 483-kilometer-wide region may be a "hot” (infrared-bright) spot on Titan is the type of enigmatic feature that is best investigated by putting together as many different types of complementary information as possible. Cassini's varied array of scientific instruments is equal to the task. This montage shows the spot in infrared wavelengths from the visual and infrared mapping spectrometer on the left, from the imaging science subsystem in the centre, and a combination of both data sets on the right.
When put together, the two different views show more than either does separately. The visual and infrared spectrometer team noted the bright region in the image on the left after Cassini's March 31, 2004, Titan encounter.
"At first glance, I thought the feature looked strange, almost out of place. After thinking a bit, I speculated that it was a hot spot. In retrospect, that might not be the best hypothesis. But the spot is no less intriguing." - Dr. Robert H. Brown, team leader of the Cassini visual and infrared mapping spectrometer and professor at the Lunar and Planetary Laboratory, University of Arizona, Tucson.


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The strange, bright feature to the southeast of Xanadu was flagged as unusual and informally dubbed "The Smile" by imaging team members in December 2004. Together the images show that The Smile (seen by the imaging cameras at 0.938 micron) bounds the infrared "Bright, Red Spot" toward the southeast. The bright region seen in the visible and infrared mapping spectrometer image extends several hundred kilometres to the north and west of The Smile, but does not cover the dark terrain located between this area and Xanadu farther to the northwest. The Smile feature also seems to extend farther west at the south end than the Bright, Red Spot.
Cassini's imaging cameras saw a bright, 550-kilometer-wide semi-circle at visible wavelengths at this same location on Cassini's December 2004 and February 2005 Titan flybys.
"It seems clear that both instruments are detecting the same basic feature on or controlled by Titan's surface." - Dr. Alfred S. McEwen, Cassini imaging team scientist, also of the University of Arizona.
This bright patch may be due to an impact event, landslide, cryovolcanism, or atmospheric processes. Its distinct color and brightness suggest that it may have formed relatively recently.
The spot might be mountains. If so, they'd have to be much higher than the 100-meter-high hills Cassini's radar altimeter has seen so far. Scientists doubt that Titan's crust could support such high mountains.

"It's possible that the visual and infrared spectrometer is seeing a cloud that is topographically controlled by something on the surface, and that this weird, semi-circular feature is causing this cloud. Titan's surface seems to be mostly dirty ice. The bright spot might be a region with different surface composition, or maybe a thin surface deposit of non-icy material," - Dr. Elizabeth Turtle, Cassini imaging team associate, also from the Lunar and Planetary Laboratory.
The false-colour image on the left was created using images taken at 1.7 microns (represented by blue), 2.0 microns (green), and 5.0 microns (red). The images that comprise this view were taken by the visual and infrared mapping spectrometer instrument on the April 16, 2005, Titan flyby. Several views were stitched together to make a mosaic. The result was then re-projected to simulate the view from the imaging camera so that the two could be directly compared.
"If the spot is a cloud, then its longevity and stability imply that it is controlled by the surface. Such a cloud might result from airflow across low mountains or out-gassing caused by geologic activity," - Jason Barnes, a postdoctoral researcher working with the visual and infrared mapping spectrometer team at the University of Arizona.
The centre image was taken by the narrow-angle camera on December 10, 2004, using a spectral filter centred at 0.938 microns (938 nanometres). The image was taken at a distance of 1.5 million kilometres from Titan and has a pixel scale of 9 kilometres per pixel. The image is centred on 8 degrees south latitude, 112 degrees west longitude. This image has been contrast enhanced and sharpened to improve surface feature visibility.

The visual and infrared mapping spectrometer team will be able to test the hot spot hypothesis on the July 2, 2006, Titan flyby, when they take night-time images of the same area. If the spot glows at night, researchers will know it's hot.



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