Dramatic plumes, both large and small, spray water ice out from many locations along the famed 'tiger stripes' near the south pole of Saturn's moon Enceladus. The tiger stripes are fissures that spray icy particles, water vapor and organic compounds.This mosaic was created from two high-resolution images that were captured by the narrow-angle camera when NASA's Cassini spacecraft flew past Enceladus and through the jets on Nov. 21, 2009. Imaging the jets over time will allow Cassini scientists to study the consistency of their activity.
Cassini on mission..
Debussey: Clair de Lune..
In this unique mosaic image combining high-resolution data from the imaging science subsystem and composite infrared spectrometer aboard NASA's Cassini spacecraft, pockets of heat appear along one of the mysterious fractures in the south polar region of Saturn's moon Enceladus. The fracture, named Baghdad Sulcus, is one of the so-called "tiger stripe" features that erupt with jets of water vapor and ice particles. It runs diagonally across the image.This mosaic, obtained on Nov. 21, 2009, shows a 40-kilometer (25-mile) segment of Baghdad Sulcus and illustrates the correlation between the geologically youthful surface fractures and anomalously warm temperatures recorded in the south polar region. It shows the highest-resolution data yet of the heat leaking from the moon's interior along the tiger stripes.
The image shows that broad swaths of heat previously detected by the infrared spectrometer are confined to a narrow, intense region no more than a kilometer (half a mile) wide along the fracture. The thermal image also reveals that the strength of the thermal radiation varies considerably along the length of this fissure segment. The temperature along Baghdad Sulcus reached more than 180 Kelvin (about minus 140 degrees Fahrenheit).
This mosaic layers temperature data atop of a visible-light image and alignment of the two data sets is approximate. The mosaic is centered near 80 degrees south latitude and 30 degrees west longitude. The V-shaped valleys that distinguish Baghdad are about 500 meters (1,600 feet) deep. The 30-degree slopes that rise along the valleys appear to be coated with smooth-looking particulate deposits that are peppered with large ice blocks that can reach tens of meters (yards) in size. The smooth materials most likely represent ice grain fallout from active jets that erupt along this warm and active section of Baghdad. The ice blocks appear to be icy rubble that may have been exposed by scouring from the eruptions, seismic shaking, and down-slope settling of the finer ice particles.
The moon's south pole lies outside of the frame of the mosaic, in the darkness below what is shown here. The full-length of Baghdad Sulcus, one of the longest tiger stripes, stretches about 175 kilometers (109 miles) all the way across the south polar region. This high-resolution view focuses only on one end of the rift, in the hemisphere that always faces toward Saturn. The other end of Baghdad was in shadow when these images were obtained. See PIA11679 to see all of Baghdad Sulcus and the other tiger stripes.
At the end of the Baghdad Sulcus segment shown here, a distinct branching pattern of fractures can be seen forking away from the central rift. The main fissure and the branching rifts slice through a complex system of quasi-parallel, rope-like, rounded ridges each as large as a kilometer (half a mile) across and hundreds of meters (yards) in height. At scales of tens to hundreds of meters (tens to hundreds of yards), a fine network of small parallel cracks are pervasive, slicing through the valley walls of Baghdad as well as through the ropey ridges. Near the very top of the mosaic, the ropey terrain transitions to a distinctly different zone in which a complicated network of fractures subdivides a broad plain into complex polygonal patterns created by tectonics.
The temperature data shows how the surface glows at 10 to 16 micron wavelength radiation along this segment of Baghdad Sulcus, covering a region about 10 kilometers to 5 kilometers (6 miles to 3 miles) in width, with the smallest features on the thermal map measuring less than 1 kilometer (half a mile) across. The best previous map (PIA10361 and the left-hand side of PIA12448) showed details no smaller than about 5 to 9 kilometers (3 to 6 miles) across. Other previous heat maps can be seen at PIA06433 and PIA09037.
The brightest colors in the map do not correspond directly to higher temperatures, but rather to a combination of higher temperatures and larger areas of warm surface material. The intensity of heat radiation increases as the color shades from violet to red to orange to yellow. No internal heat was detected in the darkest violet regions. Uncolored regions were not mapped by Cassini's composite infrared spectrometer instrument.
While the heat appears to emanate mostly from the main Baghdad tiger stripe, some of the fractures branching off or parallel to it also appear warmer and active to varying degrees, though this needs to be confirmed by further analysis. The total amount of infrared energy and the relative amounts given off at different wavelengths show that the highest temperatures along Baghdad Sulcus are limited to a region no more than tens of meters (yards) across. Most of the heat measured by the infrared spectrometer probably arises from the warm flanks of the active fractures, rather than their central fissures. The narrow central fissure is probably even warmer than the 180 Kelvin (minus 140 degrees Fahrenheit) detected – possibly warm enough for liquid water in the fractures to be the source of the observed jets.
Four narrow-angle-camera images were re-projected to create the polar stereographic mosaic with a center latitude of 90 degrees south latitude and with the prime meridian, or 0 degrees west longitude, pointing up in the image. The seams in the mosaic are unavoidable due to change in viewing angle from image to image. The visible light images and the spectrometer data were both obtained at distances ranging from approximately 2,000 kilometers (1,200 miles) to 3,000 kilometers (1,800 miles) from Enceladus. The sun-Enceladus-spacecraft, or phase, angles vary between 135 and 90 degrees. The resolution of this mosaic is approximately 12 meters per pixel at the south pole. This view shows the side of Enceladus (504 kilometers, or 313 miles in diameter) that faces toward Saturn.
Planetary scientists have been puzzling for years over the honeycomb patterns and flat valleys with squiggly edges evident in radar images of Saturn's moon Titan. Now, working with a "volunteer researcher" who has put his own spin on data from NASA's Cassini spacecraft, they have found some recognizable analogies to a type of spectacular terrain on Earth known as karst topography. A poster session today, Thursday, March 4, at the Lunar and Planetary Science Conference in The Woodlands, Texas, displays their work.Karst terrain on Earth occurs when water dissolves layers of bedrock, leaving dramatic rock outcroppings and sinkholes. Comparing images of White Canyon in Utah, the Darai Hills of Papua New Guinea, and Guangxi Province in China to an area of connected valleys and ridges on Titan known as Sikun Labyrinthus yields eerie similarities. The materials may be different – liquid methane and ethane on Titan instead of water, and probably some slurry of organic molecules on Titan instead of rock – but the processes are likely quite similar.
"Even though Titan is an alien world with much lower temperatures, we keep learning how many similarities there are to Earth," said Karl Mitchell, a Cassini radar team associate at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "The karst-like landscape suggests there is a lot happening right now under the surface that we can't see."
Indeed, Mitchell said, if the karst landscape on Titan is consistent with Earth's, there could very well be caves under the Titan surface.
Work on these analogies was spearheaded by Mike Malaska of Chapel Hill, N.C., an organic chemist by trade and a contributor in his spare time to unmannedspaceflight.com, a Web site for amateur space enthusiasts to try their hand at visualizing NASA data. Malaska approached radar team member Jani Radebaugh at Brigham Young University in Provo, Utah, about collaborative work after meeting her at last year's Lunar and Planetary Science Conference.
"I've been in love with Titan since Cassini beamed down the first images of Titan's Shangri-La sand sea," Malaska said. "It's been amazing for the public to see data come down so quickly and get data sets so rich that you can practically imagine riding along with the spacecraft."
Abundant evidence for flowing liquids is seen in this image, from sinuous, wide river channels to shorter, more chaotic drainage patterns. The extremely dissected, rugged terrain in the southern portion of the image has been very eroded by flowing liquids, probably from a combination of methane rainstorms and sapping (subsurface methane rising to erode the surface). The broad valleys seen in the southern portion of the image are particularly intriguing, as they appear to be flat-floored, filled with smooth material, and in places have sharply defined, relatively straight sides. Valleys such as this can be formed by tectonic processes, such as rifting, or by erosional processes, caused by flowing liquid or ice.
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Now we shift our attention to one of the beautiful moons of Jupiter.. Europa!
Most planetary scientists believe that a layer of liquid water exists beneath Europa's surface, kept warm by tidally-generated heat. The heating by radioactive decay, which is almost the same as in Earth (per kg of rock), cannot provide necessary heating in Europa because the volume-to-surface ratio is much lower due to the moon's smaller size.
Europa's surface temperature averages about 110 K (−160 °C; −260 °F) at the equator and only 50 K (−220 °C; −370 °F) at the poles, keeping Europa's icy crust as hard as granite. The first hints of a subsurface ocean came from theoretical considerations of tidal heating (a consequence of Europa's slightly eccentric orbit and orbital resonance with the other Galilean moons).
Galileo imaging team members argue for the existence of a subsurface ocean from analysis of Voyager and Galileo images.The most dramatic example is "chaos terrain", a common feature on Europa's surface that some interpret as a region where the subsurface ocean has melted through the icy crust. This interpretation is extremely controversial.
Most geologists who have studied Europa favor what is commonly called the "thick ice" model, in which the ocean has rarely, if ever, directly interacted with the present surface. The different models for the estimation of the ice shell thickness give values between a few kilometers and tens of kilometers.
The CIRS(Composite Infrared Spectrometer) is a remote sensing instrument that measures the infrared waves coming from objects to learn about their temperatures, thermal properties, and compositions.
Throughout the Cassini–Huygens mission, the CIRS will measure infrared emissions from atmospheres, rings and surfaces in the vast Saturn system. It will map the atmosphere of Saturn in three dimensions to determine temperature and pressure profiles with altitude, gas composition, and the distribution of aerosols and clouds. It will also measure thermal characteristics and the composition of satellite surfaces and rings.
The investigation by Cassini's radio science team suggests that Titan's interior is a cool mix of ice studded with rock, though the outermost 500 kilometers (300 miles) appear to be ice essentially devoid of any rock. Many planets and moons, including the Earth, evolve into a body with a clearly distinct rocky core. This radio science investigation suggests Titan's interior, cool and sluggish, failed to allow the interior to separate into completely differentiated layers of ice and rock.
In addition to the hazy surface of Titan (yellow), the layers in the cutaway show an ice layer starting near the surface (light gray), an internal ocean hypothesized from other Cassini data (blue), another layer of ice (light gray) and the mix of rock and ice in the interior (dark gray). In the background are the Cassini spacecraft and Saturn, not to scale.
In addition to the hazy surface of Titan (yellow), the layers in the cutaway show an ice layer starting near the surface (light gray), an internal ocean hypothesized from other Cassini data (blue), another layer of ice (light gray) and the mix of rock and ice in the interior (dark gray). In the background are the Cassini spacecraft and Saturn, not to scale.
where is Cassini now as of Mar 12 2010?
Jupiter is the biggest planet in our solar system..
orbit of the planet around the sun gets lot bigger as it further apart from the sun..
beautiful beautiful Mars.. brother planet of Earth
orbit of the planet around the sun gets lot bigger as it further apart from the sun.. 
beautiful beautiful Mars.. brother planet of Earth
Credit of images, illustrations, descriptions & everything : NASA/JPL
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