Galerie de photos d'Encelade, satellite de la planète Saturne

PIA09786: Enceladus Afar	PIA09791: Off Saturn's Shoulder
PIA09882: On Approach to Enceladus	$<h1>PIA10351: Ancient Cratered Terrains on Enceladus—A Complex Deformation History</h1><div class="PIA10351" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The topography of planetary surfaces tells us much about the geologic history and forces involved, and volcanically active Enceladus is no exception. New topographic maps give us a fresh unprecedented look at this tortured moon. This perspective view shows the oldest most heavily cratered terrains on the surface. Long ridges and grooves and numerous younger narrow parallel fractures cut across many of these craters, showing that even this ancient terrain has not escaped the extensive tectonic deformation that has wracked this small icy moon. The larger craters in the foreground are typically 2 kilometers across and a few hundred meters deep. This perspective view was constructed from digital elevation models produced by Dr. Paul Schenk (<a href="http://www.lpi.usra.edu/lpi/schenk/" class="external free" target="wpext">http://www.lpi.usra.edu/lpi/schenk/</a>) at the Lunar and Planetary Institute in Houston, TX, based on stereo and shape-from-shading analysis of Cassini images acquired in March 2005. Vertical relief has been exaggerated by a factor of 10 to aid interpretation. </p><p>The raw data from which this product was developed were retrieved from the Planetary Data System's Cassini archives. 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. (<a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>)<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA10351" onclick="window.open(this.href); return false;" title="Voir l'image PIA10351: Ancient Cratered Terrains on Enceladus—A Complex Deformation History sur le site de la NASA">Voir l'image PIA10351: Ancient Cratered Terrains on Enceladus—A Complex Deformation History sur le site de la NASA.</a></div>$ PIA10351: Ancient Cratered Terrains on Enceladus—A Complex Deformation History
$<h1>PIA10352: Tiger Stripes on Enceladus—Fracture Zones and Plumes Sources</h1><div class="PIA10352" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The plumes of water and other ice vapors jetting from the surface of Enceladus are one of the most exciting astronomical discoveries of the 21st century. These plumes originate from long linear fractures near the south pole of Enceladus. New topographic maps give us a fresh unprecedented look at this geologically young and active region. This perspective view shows several of these tiger stripes from which the plumes are venting. The stripes themselves consist of deep grooves flanked by two elevated ridges. The south polar terrains generally are also heavily fractured and deformed. These new topographic maps, constructed from stereo and shape-from-shading techniques by Dr. Paul Schenk (<a href="http://www.lpi.usra.edu/lpi/schenk/" class="external free" target="wpext">http://www.lpi.usra.edu/lpi/schenk/</a>) at the Lunar and Planetary Institute, show that the stripes do not have a lot of relief. The flanking ridges are typically 75 to 200 meters high while the grooves in between the ridges are 150 to 300 meters deep. Intensely deformed ridges along the edge of the south polar terrains (lower right) have relief of up to 1 kilometer or so. Vertical relief has been exaggerated by a factor of 20 in this view to aid interpretation. </p><p>The raw data from which this product was developed were retrieved from the Planetary Data System's Cassini archives. 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. (<a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>)<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA10352" onclick="window.open(this.href); return false;" title="Voir l'image PIA10352: Tiger Stripes on Enceladus—Fracture Zones and Plumes Sources sur le site de la NASA">Voir l'image PIA10352: Tiger Stripes on Enceladus—Fracture Zones and Plumes Sources sur le site de la NASA.</a></div>$ PIA10352: Tiger Stripes on Enceladus—Fracture Zones and Plumes Sources	PIA10354: Stellar Data on Plume
$<h1>PIA10403: Icy Oasis</h1><div class="PIA10403" lang="en" style="width:260px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>With its excess warmth, water ice jets and huge vapor plume laced with simple organic materials, Enceladus is an important part of the quest to understand environments compatible with the chemistry of life as we know it. The sulci, or "tiger stripe" fractures, in the south polar region are visible at bottom -- the view here is parallel to the direction of the sulci.</p><p>The view looks toward the anti-Saturn hemisphere on the moon's trailing side. North on Enceladus (504 kilometers, or 313 miles across) is towards the top of the image.</p><p>This false-color view is a composite of individual frames obtained using filters sensitive to ultraviolet (centered at 338 nanometers), green (centered at 568 nanometers) and infrared light (centered at 1002 nanometers). The broad range of wavelengths exaggerates subtle color variations across the moon's surface.</p><p>The images were acquired with the Cassini spacecraft narrow-angle camera on May 11, 2008. The view was obtained at a distance of approximately 739,000 kilometers (459,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 36 degrees. Image scale is 4 kilometers (3 miles) per pixel.</p><p>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.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA10403" onclick="window.open(this.href); return false;" title="Voir l'image PIA10403: Icy Oasis sur le site de la NASA">Voir l'image PIA10403: Icy Oasis sur le site de la NASA.</a></div>$ PIA10403: Icy Oasis	PIA10422: Crescent Enceladus
$<h1>PIA10436: Distant Details on Enceladus</h1><div class="PIA10436" lang="en" style="width:539px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Interesting geological details on Enceladus can be seen in modest-resolution Cassini spacecraft views like this one. At bottom is the wrinkled and generally crater-free terrain near the moon's south pole, which contains the actively venting "tiger stripe" fractures. </p><p>Multiple funnel-shaped tectonic patterns are visible above (north of) the polar region; in higher resolution Cassini images these are seen to be folded regions of ridges and troughs (see <a href="/catalog/PIA06191">PIA06191</a>). North of these features are long, north-south trending fractures.</p><p>The view looks toward the southern hemisphere on the trailing side of Enceladus (504 kilometers, or 313 miles across).The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on May 26, 2008 at a distance of approximately 516,000 kilometers (320,000 miles) from Enceladus. Image scale is 3 kilometers (2 miles) per pixel.</p><p>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.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA10436" onclick="window.open(this.href); return false;" title="Voir l'image PIA10436: Distant Details on Enceladus sur le site de la NASA">Voir l'image PIA10436: Distant Details on Enceladus sur le site de la NASA.</a></div>$ PIA10436: Distant Details on Enceladus	$<h1>PIA10445: Reshaping the Craters</h1><div class="PIA10445" lang="en" style="width:799px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Craters on Enceladus tend to be modified by a couple of different processes that are visible in this view. </p><p>Most crater rims on this icy surface appear to have softened, or "relaxed," shapes compared to the initial, sharp edges they likely possessed when first formed by impacts. Additionally, systems of tectonic folds and fractures cut through craters, like those at top center, repaving the more ancient, cratered surface. </p><p>One of the largest of these systems is Samarkand Sulci, which stretches from lower right toward upper left in this view.</p><p>The view looks toward terrain near the north pole of Enceladus (504 kilometers, or 313 miles across) from 48 degrees above the moon's equator. Lit terrain seen here is on the moon's Saturn-facing side. North is up and rotated 16 degrees to the left.</p><p>The image was taken with the Cassini spacecraft narrow-angle camera on June 30, 2008 using a combination of spectral filters sensitive to wavelengths of polarized green light centered at 617 and 568 nanometers. The view was acquired at a distance of approximately 161,000 kilometers (100,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 85 degrees. Image scale is 962 meters (0.6 mile) per pixel.</p><p>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.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA10445" onclick="window.open(this.href); return false;" title="Voir l'image PIA10445: Reshaping the Craters sur le site de la NASA">Voir l'image PIA10445: Reshaping the Craters sur le site de la NASA.</a></div>$ PIA10445: Reshaping the Craters
PIA10471: Approaching Enceladus	PIA10473: White Moon
PIA10483: Youthful Wrinkles	PIA10485: Focus on Enceladus
PIA10498: Just a Phase	PIA10500: Occulting Enceladus
PIA10502: Plumewatch	PIA10515: Over the Limb
PIA10526: Starry Night	PIA10551: Enceladus in Eclipse
PIA11105: Enceladus Rev 80 Flyby Skeet Shoot #1	PIA11106: Enceladus Rev 80 Flyby Skeet Shoot #3
PIA11107: Enceladus Rev 80 Flyby Skeet Shoot #7	PIA11108: Enceladus Rev 91 Flyby - Skeet Shoot #4
$<h1>PIA11109: Enceladus Rev 80 Flyby Skeet Shoot #4</h1><div class="PIA11109" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image is the fourth skeet-shoot footprint taken during Cassini's very close flyby of Enceladus on Aug. 11, 2008. Cairo Sulcus is shown crossing the upper left portion of the image. An unnamed fracture curves around the lower right corner. (The image is upside down from the skeet-shoot footprint shown here.) The image was taken with the Cassini spacecraft narrow-angle camera on Aug. 11, 2008, a distance of approximately 3,027 kilometers (1,881 miles) above the surface of Enceladus. Image scale is approximately 20 meters (66 feet) per pixel.</p><p>The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA11109" onclick="window.open(this.href); return false;" title="Voir l'image PIA11109: Enceladus Rev 80 Flyby Skeet Shoot #4 sur le site de la NASA">Voir l'image PIA11109: Enceladus Rev 80 Flyby Skeet Shoot #4 sur le site de la NASA.</a></div>$ PIA11109: Enceladus Rev 80 Flyby Skeet Shoot #4	$<h1>PIA11112: Great Southern Land</h1><div class="PIA11112" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p><a href="/figures/PIA11112_fig1.jpg" class="external free" target="wpext"></a><br />Annotated version</p><p>This sweeping mosaic of Saturn's moon Enceladus provides broad regional context for the ultra-sharp, close-up views NASA's Cassini spacecraft acquired minutes earlier, during its flyby on Aug. 11, 2008. See <a href="/catalog/PIA11114">PIA11114</a> and <a href="/catalog/PIA11113">PIA11113</a> for the higher resolution views.</p><p>This false-color mosaic combines Imaging Science Subsystem (ISS) narrow-angle camera images obtained through ultraviolet, green, and near-infrared camera filters. Areas that are greenish in appearance are believed to represent deposits of coarser grained ice and solid boulders that are too small to be seen at this scale, but which are visible in the higher resolution views, while whitish deposits represent finer grained ice. The mosaic shows that coarse-grained and solid ice are concentrated along valley floors and walls, as well as along the upraised flanks of the "tiger stripe" fractures, which may be covered with plume fallout that landed not far from the sources. Elsewhere on Enceladus, this coarse water ice is concentrated within outcrops along cliff faces and at the top of ridges. The sinuous boundary of scarps and ridges that encircles the south polar terrain at about 55 degrees south latitude is conspicuous. Much of the coarse-grained or solid ice along this boundary may be blocky rubble that has crumbled off of cliff faces as a result of ongoing seismic activity. This mosaic complements the imaging coverage acquired during Cassini's July 2005 flyby of Enceladus by showing portions of the moon's south polar region and tiger stripes, or sulci, that were in darkness during that flyby (<a href="/catalog/PIA06247">PIA06247</a>). </p><p>The reversed lighting conditions over the polar region (compared to the July 2005 images) highlight features, such as fractures and ridges, that are barely visible in the July 2005 views, and vice versa. The four most prominent sulci (from top to bottom: Damascus, Baghdad, Alexandria and Cairo) appear as generally horizontal fractures near lower right, and they extend into the moon's night side. The mosaic is an orthographic projection centered at 63.0 degrees south latitude, 281.3 degrees west longitude, and has an image scale of 60 meters (196 feet) per pixel. The original images ranged in resolution from 28 to 154 meters (92 to 505 feet) per pixel and were taken at distances ranging from 5,064 to 25,949 kilometers (3,140 to 15,468 miles) from Enceladus.</p><p>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.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA11112" onclick="window.open(this.href); return false;" title="Voir l'image PIA11112: Great Southern Land sur le site de la NASA">Voir l'image PIA11112: Great Southern Land sur le site de la NASA.</a></div>$ PIA11112: Great Southern Land
$<h1>PIA11113: Damascus Sulcus on Enceladus</h1><div class="PIA11113" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p><a href="/archive/PIA11113_fig1.tif" class="external free" target="wpext"></a><br />High resolution annotated version</p><p>Cassini shot past the surface of Saturn's moon Enceladus on Aug. 11, 2008, acquiring a set of seven high-resolution images targeting known jet source locations on the moon's "tiger stripe" fractures, or sulci. Two of those images are presented in this mosaic; the other five images are shown in <a href="/catalog/PIA11114">PIA11114</a>.</p><p>Features on Enceladus are named for characters and places from "The Arabian Nights," and the four most prominent sulci are named Alexandria, Cairo, Baghdad and Damascus. Here, Damascus Sulcus runs across the center, from left to right.</p><p>One highly anticipated result of this flyby was to pinpoint previously identified source locations for the jets that blast icy particles, water vapor and trace organics into space (see <a href="/catalog/PIA08385">PIA08385</a>). The yellow circles on the annotated version of the mosaic indicate source locations II and III identified in <a href="/catalog/PIA08385">PIA08385</a>).</p><p>Scientists are using these new images to study geologic activity associated with the sulci, and effects on the surrounding terrain. This information, coupled with observations by Cassini's other instruments, may answer the question of whether reservoirs of liquid water exist beneath the surface. </p><p>The mosaic consists of two images obtained with the clear spectral filters on Cassini's narrow-angle camera. The view is an orthographic projection with an image scale of 24 meters (79 feet) per pixel. The area shown here is centered on 81.2 degrees south latitude, 309.9 degrees west longitude. The original images ranged in resolution from 27 to 30 meters (89 to 98 feet) per pixel and were taken at distances ranging from 4,200 to 4,742 kilometers (2,610 to 2,947 miles) from Enceladus.</p><p>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.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA11113" onclick="window.open(this.href); return false;" title="Voir l'image PIA11113: Damascus Sulcus on Enceladus sur le site de la NASA">Voir l'image PIA11113: Damascus Sulcus on Enceladus sur le site de la NASA.</a></div>$ PIA11113: Damascus Sulcus on Enceladus	$<h1>PIA11114: Baghdad and Cairo Sulci on Enceladus</h1><div class="PIA11114" lang="en" style="width:744px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p><a href="/archive/PIA11114_fig1.tif" class="external free" target="wpext"></a><br />High resolution annotated version</p><p>Cassini shot past the surface of Saturn's moon Enceladus on Aug. 11, 2008, acquiring a set of seven high-resolution images targeting known jet source locations on the moon's "tiger stripe" fractures, or sulci. </p><p>Five of those images are presented in this mosaic; the other two images are shown in <a href="/catalog/PIA11113">PIA11113</a>. Features on Enceladus are named for characters and places from "The Arabian Nights," and the four most prominent sulci are named Alexandria, Cairo, Baghdad and Damascus. Here, Baghdad Sulcus runs across the top mosaic tile, from lower left to upper right. Cairo Sulcus runs from left to right just beneath the center tile. </p><p>One highly anticipated result of this flyby was to pinpoint previously identified source locations for the jets that blast icy particles, water vapor and trace organics into space (see <a href="/catalog/PIA08385">PIA08385</a>). The yellow circles on the annotated version of the mosaic indicate source locations I and V identified in <a href="/catalog/PIA08385">PIA08385</a>. </p><p>Scientists are using these new images to study geologic activity associated with the sulci, and effects on the surrounding terrain. This information, coupled with observations by Cassini's other instruments, may answer the question of whether reservoirs of liquid water exist beneath the surface.</p><p>The mosaic consists of five images taken with the clear spectral filters on Cassini's narrow-angle camera. The view is an orthographic projection with an image scale of 14.5 meters (47.5 feet) per pixel. The area shown here is centered on 81.6 degrees south latitude, 56.5 degrees west longitude. The original images ranged in resolution from 10 to 24 meters (33 to 79 feet) per pixel and were taken at distances ranging from 1,288 to 3,600 kilometers (800 to 2,237 miles) from Enceladus.</p><p>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.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov" class="external free" target="wpext">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org" class="external free" target="wpext">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA11114" onclick="window.open(this.href); return false;" title="Voir l'image PIA11114: Baghdad and Cairo Sulci on Enceladus sur le site de la NASA">Voir l'image PIA11114: Baghdad and Cairo Sulci on Enceladus sur le site de la NASA.</a></div>$ PIA11114: Baghdad and Cairo Sulci on Enceladus
PIA11119: Enceladus Oct. 9, 2008 Flyby - Posted Image #1	PIA11120: Enceladus Oct. 9, 2008 Flyby - Posted Image #2

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