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Iapetus: Saturn's Walnut-shaped Moon


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#16    Waspie_Dwarf

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Posted 12 September 2007 - 09:40 PM

Close-Up of Iapetus
09.11.07

linked-image

This is a raw, or unprocessed, image taken by the Cassini spacecraft during its close flyby of Saturn's moon Iapetus on September 10.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: Image credit: NASA/JPL/Space Science Institute

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Source: NASA - Missions - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#17    Waspie_Dwarf

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Posted 12 September 2007 - 09:44 PM

Close-Up of Iapetus
09.12.07

linked-image

This is a raw, or unprocessed, image taken by the Cassini spacecraft during its close flyby of Saturn's moon Iapetus on September 10.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: Image credit: NASA/JPL/Space Science Institute

+ Full resolution

Source: NASA - Missions - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#18    Waspie_Dwarf

Waspie_Dwarf

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Posted 12 September 2007 - 09:46 PM

Close-Up of Iapetus
09.12.07

linked-image

This is a raw, or unprocessed, image taken by the Cassini spacecraft during its close flyby of Saturn's moon Iapetus on September 10.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: Image credit: NASA/JPL/Space Science Institute

+ Full resolution

Source: NASA - Missions - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#19    Waspie_Dwarf

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Posted 12 September 2007 - 09:47 PM

Close-Up of Iapetus
09.12.07

linked-image

This is a raw, or unprocessed, image taken by the Cassini spacecraft during its close flyby of Saturn's moon Iapetus on September 10.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: Image credit: NASA/JPL/Space Science Institute

Source: NASA - Missions - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#20    Waspie_Dwarf

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Posted 13 September 2007 - 04:31 PM

linked-image

The Himalayas of Iapetus
September 12, 2007

This stunning close-up view shows mountainous terrain that reaches about 10 kilometers (6 miles) high along the unique equatorial ridge of Iapetus. The view was acquired during Cassini's only close flyby of the two-toned Saturn moon.

Above the middle of the image can be seen a place where an impact has exposed the bright ice beneath the dark overlying material.

The image was taken on Sept. 10, 2007, with the Cassini spacecraft narrow-angle camera at a distance of approximately 3,870 kilometers (2,400 miles) from Iapetus. Image scale is 23 meters (75 feet) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#21    Waspie_Dwarf

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Posted 13 September 2007 - 04:33 PM

linked-image

Inky Stains on a Frozen Moon
September 12, 2007

Dark material splatters the walls and floors of craters in the surreal, frozen wastelands of Iapetus. This image shows terrain in the transition region between the moon's dark leading hemisphere and its bright trailing hemisphere. The view was acquired during Cassini's only close flyby of the two-toned Saturn moon.

The image was taken on Sept. 10, 2007, with the Cassini spacecraft narrow-angle camera at a distance of approximately 6,030 kilometers (3,750 miles) from Iapetus. Image scale is 36 meters (118 feet) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#22    Waspie_Dwarf

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Posted 13 September 2007 - 04:42 PM

Saturn's Moon Iapetus Is the Yin-and-Yang of the Solar System
09.12.07

PASADENA, Calif. - Scientists on the Cassini mission to Saturn are poring through hundreds of images returned from the Sept. 10 flyby of Saturn's two-toned moon Iapetus. Pictures returned late Tuesday and early Wednesday show the moon's yin and yang--a white hemisphere resembling snow, and the other as black as tar.

Images show a surface that is heavily cratered, along with the mountain ridge that runs along the moon's equator. Many of the close-up observations focused on studying the strange 20-kilometer high (12 mile) mountain ridge that gives the moon a walnut-shaped appearance.

linked-image
Image above: Cassini surveys a bright landscape coated by dark material
on Iapetus. This image shows terrain in the transition region between the
moon’s dark leading hemisphere and its bright trailing hemisphere.
Image credit: NASA/JPL/Space Science Institute


"The images are really stunning," said Tilmann Denk, Cassini imaging scientist at the Free University in Berlin, Germany, who was responsible for the imaging observation planning. "Every new picture contained its own charm. I was most pleased about the images showing huge mountains rising over the horizon. I knew about this scenic viewing opportunity for more than seven years, and now the real images suddenly materialized."

This flyby was nearly 100 times closer to Iapetus than Cassini's 2004 flyby, bringing the spacecraft to about 1,640 kilometers (1,000 miles) from the surface. The moon's irregular walnut shape, the mountain ridge that lies almost directly on the equator and Iapetus' brightness contrast are among the key mysteries scientists are trying to solve.

"There's never a dull moment on this mission," said Bob Mitchell, Cassini program manager, NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We are very excited about the stunning images being returned. There's plenty here to keep many scientists busy for many years."

"Our flight over the surface of Iapetus was like a non-stop free fall, down the rabbit hole, directly into Wonderland! Very few places in our solar system are more bizarre than the patchwork of pitch dark and snowy bright we've seen on this moon," said Carolyn Porco, Cassini imaging team leader at the Space Science Institute, Boulder, Colo.

linked-image
Image above: This stunning close-up view
shows mountainous terrain that reaches about
10 kilometers (6 miles) high along the unique
equatorial ridge of Iapetus.
Image credit: NASA/JPL/Space Science Institute


The return of images and other data was delayed early Tuesday due to a galactic cosmic ray hit which put the spacecraft into a precautionary state called safe mode. This occurred after the spacecraft had placed all of the flyby data on its data recorders and during the first few minutes after it began sending the data home. The data flow resumed later that day and concluded on Wednesday. The spacecraft is operating normally and its instruments are expected to return to normal operations in a few days.

"Iapetus provides us a window back in time, to the formation of the planets over four billion years ago. Since then its icy crust has been cold and stiff, preserving this ancient surface for our study," said Torrence Johnson, Cassini imaging team member at JPL.

Cassini's multiple observations of Iapetus will help to characterize the chemical composition of the surface; look for evidence of a faint atmosphere or erupting gas plumes; and map the nighttime temperature of the surface. These and other results will be analyzed in the weeks to come.

Iapetus flyby images are available at: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov and and http://ciclops.org.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

Media contact: Carolina Martinez 818-354-9382
Jet Propulsion Laboratory, Pasadena, Calif.
carolina.martinez@jpl.nasa.gov

Preston Dyches 720-974-5859
Space Science Institute, Boulder, Colo.
media@ciclops.org

2007-101


Source: NASA - Missions - Cassini - Media

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#23    Waspie_Dwarf

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Posted 13 September 2007 - 04:45 PM

Coated Craters
09.12.07

linked-image

Cassini surveys a bright landscape coated by dark material on Iapetus. This image shows terrain in the transition region between the moon’s dark leading hemisphere and its bright trailing hemisphere. The view was acquired during Cassini's only close flyby of the two-toned Saturn moon.

The image was taken on Sept. 10, 2007, with the Cassini spacecraft narrow-angle camera at a distance of approximately 5,260 kilometers (3,270 miles) from Iapetus. Image scale is 32 meters (105 feet) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: Image credit: NASA/JPL/Space Science Institute

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Source: NASA - Missions - Cassini

Edited by Waspie_Dwarf, 13 September 2007 - 04:49 PM.

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#24    Waspie_Dwarf

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Posted 13 September 2007 - 04:47 PM

The "Voyager" Mountains
09.12.07

linked-image

Cassini zooms in, for the first time, on the patchy, bright and dark mountains originally identified in images from the NASA Voyager spacecraft taken more than 25 years earlier. The image was acquired during Cassini's only close flyby of Iapetus, a two-toned moon of Saturn.

The terrain seen here is located on the equator of Iapetus at approximately 199 degrees west longitude, in the transition region between the moon's bright and dark hemispheres. North is up.

The image was taken on Sept. 10, 2007, with the Cassini spacecraft narrow-angle camera at a distance of approximately 9,240 kilometers (5,740 miles) from Iapetus. Image scale is 55 meters (180 feet) per pixell.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: Image credit: NASA/JPL/Space Science Institute

+ High resolution

Source: NASA - Missions - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#25    Waspie_Dwarf

Waspie_Dwarf

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Posted 08 October 2007 - 03:05 PM

Cassini Is on the Trail of a Runaway Mystery
10.08.07

NASA scientists are on the trail of Iapetus' mysterious dark side, which seems to be home to a bizarre "runaway" process that is transporting vaporized water ice from the dark areas to the white areas of the Saturnian moon.

This "thermal segregation" model may explain many details of the moon's strange and dramatically two-toned appearance, which have been revealed exquisitely in images collected during a recent close flyby of Iapetus by NASA's Cassini spacecraft.

linked-image
Image above: Cassini captures the first high-resolution glimpse of the
bright trailing hemisphere of Saturn's moon Iapetus in this false-color
mosaic. This false-color mosaic shows the entire hemisphere of Iapetus.
Image credit: NASA/JPL/Space Science Institute


Infrared observations from the flyby confirm that the dark material is warm enough (approximately minus 230 degrees Fahrenheit or 127 Kelvin) for very slow release of water vapor from water ice, and this process is probably a major factor in determining the distinct brightness boundaries.

"The side of Iapetus that faces forward in its orbit around Saturn is being darkened by some mysterious process," said John Spencer, Cassini scientist with the composite infrared spectrometer team from the Southwest Research Institute, Boulder, Colo.

Using multiple instruments on Cassini, scientists are piecing together a complex story to explain the bright and dark faces of Iapetus. But yet to be fully understood is where the dark material is coming from. Is it native or from outside the moon? It has long been hypothesized that this material did not originate from within Iapetus, but instead was derived from other moons orbiting at a much greater distance from Saturn in a direction opposite to Iapetus.

Scientists are now converging on the notion that the darkening process in fact began in this manner, and that thermal effects subsequently enhanced the contrast to what we see today.

linked-image
Image above: This image compares midday
temperatures on Saturn's moon Iapetus,
recorded by the composite infrared spectrometer
instrument during Cassini's close Sept. 10, 2007
flyby, with images of the same region recorded
during the same flyby by the Cassini imaging
science subsystem.
Image credit: NASA/JPL/GSFC/SwRI/SSI


"It's interesting to ponder that a more than 30-year-old idea might still help explain the brightness difference on Iapetus," said Tilmann Denk, Cassini imaging scientist at the Free University in Berlin, Germany. "Dusty material spiraling in from outer moons hits Iapetus head-on, and causes the forward-facing side of Iapetus to look different than the rest of the moon."

Once the leading side is even slightly dark, thermal segregation can proceed rapidly. A dark surface will absorb more sunlight and warm up, explains Spencer, so the water ice on the surface evaporates. The water vapor then condenses on the nearest cold spot, which could be Iapetus's poles, and possibly bright, icy areas at lower latitudes on the side of the moon facing in the opposite direction of its orbit. So the dark stuff loses its surface ice and gets darker, and the bright stuff accumulates ice and gets brighter, in a runaway process.

Scientists say the result is that there are virtually no shades of gray on Iapetus. There is only white and very dark.

Ultraviolet data also show a non-ice component in the bright, white regions of Iapetus. Spectroscopic analysis will reveal whether the composition of the material on the dark hemisphere is the same as the dark material that is present within the bright terrain.

"The ultraviolet data tell us a lot about where the water ice is and where the non-water ice stuff is. At first glance, the two populations do not appear to be present in the pattern we expected, which is very interesting," said Amanda Hendrix, Cassini scientist on the ultraviolet imaging spectrograph team at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Because of the presence of very small craters that excavate the bright ice beneath, scientists also believe that the dark material is thin, a result consistent with previous Cassini radar results. But some local areas may be thicker. The dark material seems to lie on top of the bright region, consistent with the idea that it is a residual left behind by the sublimated water ice.

Some other mysteries are coming together. There are more data on the signature mountain ridge that gives Iapetus its "walnut" appearance. In some places it appears subdued. One big question that remains is why it does not go all the way around. Was it partially destroyed after it formed, or did it never extend all the way around the moon? Scientists have ruled out that it is a youthful feature because it is pitted with craters, indicating it is old. And the ridge looks too solid and competent to be the result of an equatorial ring around the moon collapsing onto its surface. The ring theory cannot explain features that look like tectonic structures in the new high resolution images.

Over the next few months, scientists hope to learn more about Iapetus' mysteries.

New Iapetus images, temperature maps and other visuals on Iapetus are available at: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Science Mission Directorate, Washington, D.C.


Media contact: Carolina Martinez 818-354-9382
Jet Propulsion Laboratory, Pasadena, Calif.
carolina.martinez@jpl.nasa.gov

2007-113


Source: NASA - Missions - Cassini - Media

Edited by Waspie_Dwarf, 08 October 2007 - 05:33 PM.

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#26    Waspie_Dwarf

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Posted 08 October 2007 - 05:42 PM

linked-image

Approaching Iapetus
October 8, 2007

The slim crescent of Iapetus looms before the Cassini spacecraft as it approaches the mysterious moon.

Iapetus, 1,468 kilometers (912 miles) across, seen here in false color, is unique in its dramatic variation in brightness between the northern polar region and the middle and low latitudes. Equally prominent is the moon's equatorial ridge of towering mountains. The profile of the ridge against the darkness of space reveals that it is topped by a cratered plateau approximately 15 kilometers (9 miles) wide. Further west, the profile of the ridge changes from a long plateau to discrete peaks.

The mosaic consists of four image footprints across the surface of Iapetus and has a resolution of 489 meters (0.3 miles) per pixel.

A full-resolution clear filter image was combined with half-resolution images taken with infrared, green and ultraviolet spectral filters (centered at 752, 568 and 338 nanometers, respectively) to create this full-resolution false color mosaic.

The color seen in this view represents an expansion of the wavelength region of the electromagnetic spectrum visible to human eyes. The intense reddish-brown hue of the dark material is far less pronounced in true color images. The use of enhanced color makes the reddish character of the dark material more visible than it would be to the naked eye. In addition, the scene has been brightened to improve the visibility of surface features.

This view was acquired with the Cassini spacecraft narrow-angle camera on Sept. 10, 2007, at a distance of about 83,000 kilometers (51,600 miles) from Iapetus.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#27    Waspie_Dwarf

Waspie_Dwarf

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Posted 08 October 2007 - 05:56 PM

linked-image

A Scene of Craters
October 8, 2007

This high-resolution view shows a vast range of crater sizes in the dark terrain of the leading hemisphere of Saturn's moon Iapetus.

Across the scene, a few small bright spots indicate fresh, rayed craters where impactors have punched through the thin blanket of dark material to the cleaner ice beneath.

The slight elevation on the bottom half of the image is part of the giant equatorial ridge that spans a wide fraction of Iapetus' circumference. The numerous craters on top of the ridge indicate that it is an old surface feature.

The mosaic consists of three image footprints across the surface of Iapetus. The view is centered on terrain near 0.5 degrees north latitude, 141.6 degrees west longitude. Image scale is approximately 22 meters (72 feet) per pixel. Illumination is from the left.

The clear spectral filter images in this mosaic were obtained with the Cassini spacecraft narrow-angle camera on Sept. 10, 2007, at a distance of approximately 63,000 kilometers (39,000 miles) from Iapetus and at a sun-Iapetus-spacecraft, or phase, angle of about 125 degrees.

Iapetus is 1,468 kilometers (912 miles) across.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#28    Waspie_Dwarf

Waspie_Dwarf

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Posted 08 October 2007 - 05:59 PM

linked-image

Closest View of Iapetus
October 8, 2007

This mosaic of Cassini images shows the smallest details ever observed on Saturn's moon Iapetus.

Visible here are small craters as well as the base of a large mountain ridge located just south of the mosaic. At several places, bright spots about 20 to 50 meters (66 to 164 feet) across are visible. At these locations, more recent impactors have punched through the overlying blanket of dark material to reveal brighter, cleaner ice beneath.

Since the bright craters are relatively small and very shallow, it is likely that the dark blanket is rather thin in this area; it is assumed that its actual average thickness might be on the order of a foot.

The small crater at the upper left edge of the mosaic has a diameter of about 50 meters (164 feet) and shows a distinct ray pattern from excavated ice. This feature is so bright in comparison to the dark surrounding terrain that it had to be darkened manually so as not to look overexposed in this mosaic.

The mosaic consists of eight image footprints across the surface of Iapetus, presented here in simple cylindrical projection. The view is centered on terrain near 0 degrees north latitude, 164.9 degrees west longitude, within the dark leading hemisphere of Iapetus. Image scale is approximately 10 meters (33 feet) per pixel.

The clear spectral filter images in this mosaic were obtained with the Cassini spacecraft narrow-angle camera on Sept. 10, 2007, at distances ranging from 1,627 to 2,040 kilometers (1,011 to 1,268 miles) from Iapetus. Iapetus is 1,468 kilometers (912 miles) across.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#29    Waspie_Dwarf

Waspie_Dwarf

    Space Cadet

  • 34,215 posts
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  • We are all in the gutter, but some of us are looking at the stars.

    Oscar Wilde

Posted 08 October 2007 - 06:00 PM

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Towering Peaks of Iapetus
October 8, 2007

This stereo image, or anaglyph, shows huge mountains on Saturn's moon Iapetus, imaged by NASA's Cassini spacecraft during its very close flyby in Sept. 2007. These mountains are located at the moon's equator in the westward-most part of the dark terrain.

Here, the brightness pattern on the surface is very complex. The mountain in the center of this view is part of the range informally named "the Voyager mountains" that were first detected on the limb of the moon in NASA Voyager spacecraft images. Interestingly, its eastern (right) flank is dark, while the other flanks are bright. This suggests that external material arriving on Iapetus from its orbital motion might play a role in the darkening process. One plausible source, the outer moons of Saturn, might provide a very thin but steady stream of very dark particles from the eastern direction as seen from this mountain.

The mosaic consists of six image footprints across the surface of Iapetus. The view is centered on terrain near 0.1 degree north latitude, 199 degrees west longitude. Image scale is approximately 46 meters (151 feet) per pixel.

The clear spectral filter images in this mosaic were obtained with the Cassini spacecraft narrow- angle camera on Sept. 10, 2007. Distances for the blue portion of the image range from 7,744 to 9,135 kilometers (4,812 to 5,676 miles) from Iapetus; distances for the red portion of the image range from 20,267 to 21,595 kilometers (12,593 to 13,418 miles) from the moon.

A separate, non-stereo version of the scene is included for comparison.

Iapetus is 1,468 kilometers (912 miles) across.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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#30    Waspie_Dwarf

Waspie_Dwarf

    Space Cadet

  • 34,215 posts
  • Joined:03 Mar 2006
  • Gender:Male
  • Location:Bexleyheath, Kent, UK

  • We are all in the gutter, but some of us are looking at the stars.

    Oscar Wilde

Posted 08 October 2007 - 06:06 PM

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The Transition Zone
October 8, 2007

Soaring above the alien, icy wastelands of Saturn's moon Iapetus, NASA's Cassini spacecraft captured a series of high-resolution images of the transition region from dark to bright terrain at southern middle latitudes that have been mosaicked together in this view.

An important characteristic of the terrain in the boundary region is that the isolated bright patches are mainly found on slopes facing toward the bright trailing hemisphere or toward the south pole. The same polarity is found within the bright terrain, where the dark material can be seen at the bottom of craters and on equator-facing slopes. These indicate that thermal effects are at play in painting the surface of Iapetus, 1,468 kilometers (912 miles) across. The mosaic consists of eight image footprints across the surface of Iapetus. The view is centered on terrain near 38.6 degrees south latitude, 171.3 degrees west longitude. Image scale is approximately 52 meters (171 feet) per pixel.

The clear spectral filter images in this mosaic were obtained with the Cassini spacecraft narrow- angle camera on Sept. 10, 2007, at a distance of approximately 5,000 kilometers (3,100 miles) from Iapetus.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL/Space Science Institute

Source: NASA/JPL - Cassini

"Space is big. Really big. You just won't believe how vastly, hugely, mind-boggingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space." - The Hitch-Hikers Guide to the Galaxy - Douglas Adams 1952 - 2001

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