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

<h1>PIA06254: Zooming In On Enceladus (Mosaic)</h1><div class="PIA06254" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>As it swooped past the south pole of Saturn's moon Enceladus on July 14, 2005, Cassini acquired high resolution views of this puzzling ice world. From afar, Enceladus exhibits a bizarre mixture of softened craters and complex, fractured terrains.</p><p>This large mosaic of 21 narrow-angle camera images have been arranged to provide a full-disk view of the anti-Saturn hemisphere on Enceladus. This mosaic is a false-color view that includes images taken at wavelengths from the ultraviolet to the infrared portion of the spectrum, and is similar to another, lower resolution false-color view obtained during the flyby (see <a href="/catalog/PIA06249">PIA06249</a>). In false-color, many long fractures on Enceladus exhibit a pronounced difference in color (represented here in blue) from the surrounding terrain.</p><p>A leading explanation for the difference in color is that the walls of the fractures expose outcrops of coarse-grained ice that are free of the powdery surface materials that mantle flat-lying surfaces.</p><p>The original images in the false-color mosaic range in resolution from 350 to 67 meters (1,148 to 220 feet) per pixel and were taken at distances ranging from 61,300 to 11,100 kilometers (38,090 to 6,897 miles) from Enceladus. The mosaic is also part of a movie sequence of images from this flyby (see <a href="/catalog/PIA06253">PIA06253</a>).</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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a>. For additional images visit the Cassini imaging team homepage <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06254" onclick="window.open(this.href); return false;" title="Voir l'image PIA06254: Zooming In On Enceladus (Mosaic) sur le site de la NASA">Voir l'image PIA06254: Zooming In On Enceladus (Mosaic) sur le site de la NASA.</a></div>
PIA06254: Zooming In On Enceladus (Mosaic)
<h1>PIA06433: Warm Fractures on Enceladus</h1><div class="PIA06433" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image shows the warmest places in the south polar region of Saturn's moon Enceladus. The unexpected temperatures were discovered by Cassini's composite infrared spectrometer during a close flyby on July 14, 2005. The image shows how these temperatures correspond to the prominent, bluish fractures dubbed "tiger stripes," first imaged by Cassini's imaging science subsystem cameras. Working together the two teams were able to pinpoint the exact location of the warmest regions on Enceladus.</p><p>The composite infrared spectrometer instrument measured the infrared heat radiation from the surface at wavelengths between 9 and 16.5 microns within each of the 10 squares shown here. Each square is 6 kilometers (4 miles) across. The color of each square, and the number shown above it, describe the composite infrared spectrometer's measurement of the approximate average temperature of the surface within that square.</p><p>The warmest temperature squares, at 91 and 89 degrees Kelvin (minus 296 and minus 299 degrees Fahrenheit), are located over one of the "tiger stripe" fractures. They contrast sharply with the surrounding temperatures, which are in the range 74 to 81 degrees Kelvin (minus 326 to minus 313 degrees Fahrenheit). The detailed composite infrared spectrometer data suggest that small areas near the fracture are at substantially higher temperatures, well over 100 degrees Kelvin (minus 279 degrees Fahrenheit). Such "warm" temperatures are unlikely to be due to heating of the surface by the feeble sunlight striking Enceladus' south pole. They are a strong indication that internal heat is leaking out of Enceladus and warming the surface along these fractures. Evaporation of this relatively warm ice probably generates the cloud of water vapor detected above Enceladus' south pole by several other Cassini instruments. Scientists are unsure how the internal heat reaches the surface. The process might involve liquid water, slushy brine, or soft but solid ice.</p><p>The imaging science subsystem image is an enhanced color view with a pixel scale of 122 meters (400 feet) that was acquired at the same time as the composite infrared spectrometer data. It covers a region 125 kilometers (75 miles) across. The spacecraft's distance from Enceladus was 21,000 kilometers (13,000 miles). The broad bluer fractures that can be seen running from the upper left to the lower right of the image are 1 to 2 kilometers (0.6 to 1.2 miles) wide and more than 100 kilometers (60 miles) long. The fractures are thought to be bluer than the surrounding surface because coarser-grained ice (which has a blue color just as thick masses of ice, like glaciers and icebergs, do on Earth) has been exposed in the fractures. The color image was constructed using an ultraviolet filter (centered at 338 nanometers) in the blue channel, a clear filter in the green channel, and an infrared filter (centered at 930 nanometers) in the red channel.</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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. 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">http://saturn.jpl.nasa.gov</a>. The composite infrared spectrometer team homepage is <a href="http://cirs.gsfc.nasa.gov/">http://cirs.gsfc.nasa.gov/</a>. The imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a></p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06433" onclick="window.open(this.href); return false;" title="Voir l'image PIA06433: Warm Fractures on Enceladus sur le site de la NASA">Voir l'image PIA06433: Warm Fractures on Enceladus sur le site de la NASA.</a></div>
PIA06433: Warm Fractures on Enceladus
<h1>PIA06483: Ultraviolet Enceladus</h1><div class="PIA06483" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Looking beyond Saturn's south pole, this was the Cassini spacecraft's view of the distant, icy moon Enceladus on July 28, 2004. The planet itself shows few obvious features at these ultraviolet wavelengths, due to scattering of light by molecules of the gases high in the atmosphere. Enceladus is 499 kilometers (310 miles) wide.</p><p>The image was taken with the Cassini spacecraft narrow angle camera at a distance of 7.4 million kilometers (4.6 million miles) from Saturn through a filter sensitive to ultraviolet wavelengths of light. The image scale is 44 kilometers (27 miles) per pixel of Saturn.</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 Cassini-Huygens mission for NASA's Office of Space Science, 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.</p><p>For more information, about the Cassini-Huygens mission visit, <a href="http://saturn.jpl.nasa.gov/">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org/">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06483" onclick="window.open(this.href); return false;" title="Voir l'image PIA06483: Ultraviolet Enceladus sur le site de la NASA">Voir l'image PIA06483: Ultraviolet Enceladus sur le site de la NASA.</a></div>
PIA06483: Ultraviolet Enceladus
<h1>PIA06508: Atmosphere and Enceladus</h1><div class="PIA06508" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Saturn's southern atmosphere looms before Cassini, displaying rich detail in its swirls and bands. The bright, icy moon Enceladus (499 kilometers, or 310 miles across) appears near the bottom of the image.</p><p>This view was taken through a filter where methane gas is a moderate absorber of sunlight. Since methane gas is not present on Enceladus, its surface scatters a higher percentage of the light falling on it than Saturn does, making the moon appear very bright compared with the planet. Enceladus was dimmed in brightness by a factor of four during processing of the image, in order to make its brightness comparable to that of Saturn.</p><p>The rings show some fine structure here. The three main rings, C, B and A from innermost to outermost, are clearly defined by their differences in brightness.</p><p>The image was taken with the Cassini spacecraft narrow angle camera on Sept. 19, 2004, at a distance of 8.3 million kilometers (5.2 million miles) from Saturn through a filter sensitive to wavelengths of infrared light centered at 727 nanometers. The image scale is 49 kilometers (30 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 Cassini-Huygens mission for NASA's Office of Space Science, 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.</p><p>For more information, about the Cassini-Huygens mission visit, <a href="http://saturn.jpl.nasa.gov/">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org/">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06508" onclick="window.open(this.href); return false;" title="Voir l'image PIA06508: Atmosphere and Enceladus sur le site de la NASA">Voir l'image PIA06508: Atmosphere and Enceladus sur le site de la NASA.</a></div>
PIA06508: Atmosphere and Enceladus
<h1>PIA06512: Enceladus in the Distance</h1><div class="PIA06512" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini spied the moon Enceladus in the distance beyond Saturn's south pole in this image from Sept. 19, 2004.</p><p>This view was taken in wavelengths of ultraviolet light where gas molecules in Saturn's high atmosphere scatter a great deal of sunlight. Since Enceladus (499 kilometers, or 310 miles, across) has an unusually high reflectivity, its surface reflects even more of the light falling on it than Saturn does, making the moon appear very bright compared the planet. Enceladus was dimmed in brightness by a factor of three during processing of the image, in order to make its brightness comparable to that of Saturn.</p><p>The image was taken with the Cassini spacecraft narrow angle camera at a distance of 8.3 million kilometers (5.2 million miles) from Saturn. The image scale is 49 kilometers (30 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 Cassini-Huygens 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.</p><p>For more information, about the Cassini-Huygens mission visit, <a href="http://saturn.jpl.nasa.gov/">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org/">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06512" onclick="window.open(this.href); return false;" title="Voir l'image PIA06512: Enceladus in the Distance sur le site de la NASA">Voir l'image PIA06512: Enceladus in the Distance sur le site de la NASA.</a></div>
PIA06512: Enceladus in the Distance
<h1>PIA06530: Ominous Giant</h1><div class="PIA06530" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Saturn's massive atmosphere appears poised to crush little Enceladus in this image. Many fascinating details are visible in the gas planet's sinuous bands, such as a giant, eye-shaped storm that circles the south pole. The diameter of Enceladus is 499 kilometers, (310 miles).</p><p>The image was taken in visible blue light with the Cassini spacecraft narrow angle camera on Oct. 12, 2004, at a distance of about 5.3 million kilometers (3.3 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 68 degrees. The image scale is 31 kilometers (19 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 Cassini-Huygens mission for NASA's Office of Space Science, 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.</p><p>For more information, about the Cassini-Huygens mission visit, <a href="http://saturn.jpl.nasa.gov/">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org/">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06530" onclick="window.open(this.href); return false;" title="Voir l'image PIA06530: Ominous Giant sur le site de la NASA">Voir l'image PIA06530: Ominous Giant sur le site de la NASA.</a></div>
PIA06530: Ominous Giant
<h1>PIA06531: Intriguing Enceladus</h1><div class="PIA06531" lang="en" style="width:698px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This Cassini view of Enceladus hints at the curvilinear, groove-like features that crisscross the moon's surface, as seen in images from NASA's Voyager spacecraft. </p><p>The image shows the trailing hemisphere of Enceladus, which is the side opposite the moon's direction of motion in its orbit. Enceladus is 499 kilometers (310 miles) across.</p><p>The image was taken in visible light with the Cassini spacecraft narrow angle camera on Oct. 27, 2004, at a distance of about 766,000 kilometers (476,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 34 degrees. The image scale is 4.6 kilometers (2.8 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 Cassini-Huygens mission for NASA's Office of Space Science, 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.</p><p>For more information, about the Cassini-Huygens mission visit, <a href="http://saturn.jpl.nasa.gov/">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org/">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06531" onclick="window.open(this.href); return false;" title="Voir l'image PIA06531: Intriguing Enceladus sur le site de la NASA">Voir l'image PIA06531: Intriguing Enceladus sur le site de la NASA.</a></div>
PIA06531: Intriguing Enceladus
<h1>PIA06547: Saturn's Snowball</h1><div class="PIA06547" lang="en" style="width:265px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Hints of the curving linear grooves that crisscross bright, icy Enceladus are just discernible in this image captured by the Cassini spacecraft. Enceladus is almost entirely composed of water ice and has a surface as bright as snow. Its diameter is 499 kilometers (310 miles).</p><p>This view shows principally the leading hemisphere of Enceladus. The image was taken in visible light with the Cassini spacecraft narrow angle camera on Nov. 1, 2004, at a distance of 1.8 million kilometers (1.1 million miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 108 degrees. North is up. The image scale is about 11 kilometers (7 miles) per pixel. The image has been magnified by a factor of two and contrast enhanced to aid visibility of surface features.</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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information, about the Cassini-Huygens mission visit, <a href="http://saturn.jpl.nasa.gov/">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org/">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06547" onclick="window.open(this.href); return false;" title="Voir l'image PIA06547: Saturn's Snowball sur le site de la NASA">Voir l'image PIA06547: Saturn's Snowball sur le site de la NASA.</a></div>
PIA06547: Saturn's Snowball
<h1>PIA06566: Zooming In on Enceladus</h1><div class="PIA06566" lang="en" style="width:681px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini's closest look yet at bright, icy Enceladus was captured in this view, centered on the moon's trailing hemisphere. It shows some of the linear features in the terrain of the Diyar Planitia region. Enceladus is 499 kilometers (310 miles) across.</p><p>The image was taken in visible light with the Cassini spacecraft narrow angle camera on Dec. 14, 2004, at a distance of 672,000 kilometers (417,600 miles) from Enceladus and at a Sun- Enceladus-spacecraft, or phase, angle of 32 degrees. The image scale is about 4 kilometers (2.5 miles) per pixel. The image has been magnified by a factor of two and contrast enhanced to aid visibility.</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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a>. For images visit the Cassini imaging team home page <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06566" onclick="window.open(this.href); return false;" title="Voir l'image PIA06566: Zooming In on Enceladus sur le site de la NASA">Voir l'image PIA06566: Zooming In on Enceladus sur le site de la NASA.</a></div>
PIA06566: Zooming In on Enceladus
<h1>PIA06579: Bright Moon in Darkness</h1><div class="PIA06579" lang="en" style="width:664px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>In the dim light of the outer solar system, Cassini gazed back at Saturn's brightest gem - the moon Enceladus. The icy little world presents only a slim crescent in this natural color view.</p><p>Cassini has now matched the best spatial resolution on Enceladus achieved by NASA's Voyager spacecraft, and will soon have excellent coverage of the moon (at more than 10 times the resolution in this image), following a flyby planned for February 17.</p><p>When seen from its day side, Enceladus (499 kilometers, or 310 miles across) has one of the brightest and whitest surfaces in the solar system. Since it reflects most of the sunlight that strikes it, the temperature there remains at a chilly -200 degrees Celsius (-330 degrees Fahrenheit).</p><p>In this view, Cassini was pointed at the leading hemisphere of Enceladus, which was in darkness at the time. The image has been rotated so that north on Enceladus is up.</p><p>Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were acquired with the Cassini spacecraft narrow angle camera on Jan. 16, 2005, at a distance of approximately 209,300 kilometers (130,100 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 148 degrees. Resolution in the original image was about 1 kilometer (0.6 miles) per pixel. The image has been contrast-enhanced and magnified by a factor of two to aid visibility.</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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission, visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06579" onclick="window.open(this.href); return false;" title="Voir l'image PIA06579: Bright Moon in Darkness sur le site de la NASA">Voir l'image PIA06579: Bright Moon in Darkness sur le site de la NASA.</a></div>
PIA06579: Bright Moon in Darkness
<h1>PIA06581: Wrinkles of Youth?</h1><div class="PIA06581" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This Cassini image of Saturn's moon Enceladus shows a region containing bizarre, wrinkled terrain. Enceladus is covered with bright water ice. The part of its surface visible here appears to be largely free of craters - indicating that it is geologically young. </p><p>The first close imaging of this moon will be done by Cassini in February 2005 and should reveal many surprises. Enceladus has a diameter of 499 kilometers (310 miles).</p><p>This view shows primarily the leading hemisphere of Enceladus. The image has been rotated so that north on Enceladus is up.</p><p>The image was acquired with the Cassini spacecraft narrow angle camera on Jan. 15, 2005, at a distance of approximately 367,000 kilometers (228,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 74 degrees. A combination of spectral filters sensitive to infrared and polarized light was used to obtain this view. Resolution in the original image was about 2 kilometers (1.2 miles) per pixel. The image has been contrast-enhanced and magnified by a factor of two to aid visibility. </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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission, visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06581" onclick="window.open(this.href); return false;" title="Voir l'image PIA06581: Wrinkles of Youth? sur le site de la NASA">Voir l'image PIA06581: Wrinkles of Youth? sur le site de la NASA.</a></div>
PIA06581: Wrinkles of Youth?
<h1>PIA06628: Sideways Shadow</h1><div class="PIA06628" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Saturn's bright moon Enceladus hovers here, in front of a rings darkened by Saturn's shadow. Enceladus is 505 kilometers (314 miles) across.</p><p>This view is from less than one degree beneath the ring plane. If seen from directly beneath the rings, the planet's giant shadow would appear as an elongated half-ellipse; the acute viewing angle makes the shadow look more like a strip here. (See <a href="/catalog/PIA06193">PIA06193</a>, for a different viewing angle). The dark shadow first takes a bite out of the rings at the right, where the distant, outermost ring material appears to taper and fade.</p><p>Ring features visible in this image from the outer ring edge inward include: the A ring, the Cassini Division and the B ring. The C ring is the darker region that dominates the rings here. The two gaps visible near the center and below the left of the center are the Titan Gap, about 77,800 kilometers (48,300 miles) from Saturn, and an unnamed gap about 75,800 kilometers (47,100 miles) from the planet.</p><p>The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 7, 2005, at a distance of approximately 1.1 million kilometers (650,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 30 degrees. The pixel scale is 6 kilometers (4 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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission, visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a> and the Cassini imaging team home page, <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06628" onclick="window.open(this.href); return false;" title="Voir l'image PIA06628: Sideways Shadow sur le site de la NASA">Voir l'image PIA06628: Sideways Shadow sur le site de la NASA.</a></div>
PIA06628: Sideways Shadow
<h1>PIA06651: Pencil-thin Rings</h1><div class="PIA06651" lang="en" style="width:591px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>If all the material that makes up Saturn's rings were compressed into a single body, it could make a moon roughly 80 percent the size of Saturn's moon Enceladus (505 kilometers, or 314 miles across). Enceladus is seen here against the darkness of the planet's night side. </p><p>Saturn's rings are incredibly thin by astronomical standards; in most places no thicker than the height of a two-story building. Their apparent thickness here is deceptive, as Cassini is not located precisely within the ringplane, and the image resolution is greater than the physical thickness of the rings. </p><p>Long, threadlike shadows cast by the rings adorn the atmosphere in this somewhat eerie scene.</p><p>The image was taken in visible light with the Cassini spacecraft wide-angle camera on March 11, 2005, at a distance of approximately 1.3 million kilometers (800,000 miles) from Saturn. The image scale is 74 kilometers (46 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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a>. For additional images visit the Cassini imaging team homepage <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06651" onclick="window.open(this.href); return false;" title="Voir l'image PIA06651: Pencil-thin Rings sur le site de la NASA">Voir l'image PIA06651: Pencil-thin Rings sur le site de la NASA.</a></div>
PIA06651: Pencil-thin Rings
<h1>PIA06653: Bright Ice, Dirty Ice</h1><div class="PIA06653" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Saturn's icy moon Enceladus hovers above Saturn's exquisite rings in this color view from Cassini. The rings, made of nearly pure water ice, have also become somewhat contaminated by meteoritic dust during their history, which may span several hundred million years. Enceladus shares the rings' nearly pure water ice composition, but appears to have eluded dust contamination through resurfacing processes that scientists are still trying to understand. Enceladus is 505 kilometers (314 miles) across.</p><p>Dust affects the rings' color, while differences in brightness are attributable to varying particle sizes and concentrations.</p><p>The images for this natural color view were taken with the Cassini spacecraft narrow-angle camera on April 5, 2005, at a distance of approximately 2.2 million kilometers (1.4 million miles) from Saturn through red, green and blue spectral filters. The image scale is 13 kilometers (8 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 team is based at the Space Science Institute, Boulder, Colo.</p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a>. For additional images visit the Cassini imaging team homepage <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06653" onclick="window.open(this.href); return false;" title="Voir l'image PIA06653: Bright Ice, Dirty Ice sur le site de la NASA">Voir l'image PIA06653: Bright Ice, Dirty Ice sur le site de la NASA.</a></div>
PIA06653: Bright Ice, Dirty Ice
<h1>PIA07619: Iceball Among Snowballs</h1><div class="PIA07619" lang="en" style="width:791px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The moon Enceladus seems to hover above the outer reaches of Saturn's B ring. Below and to the right of Enceladus, four faint bands lie in the center of the dark Cassini Division.</p><p>Recently, scientists have speculated that the particles that make up the dense B and A rings might be more like fluffy snowballs than hard ice cubes. The conclusion is based on temperature data obtained by the Cassini spacecraft. </p><p>Enceladus' diameter is 505 kilometers (314 miles). The icy moon is on the near side of the rings in this view.</p><p>This image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 15, 2005, at a distance of approximately 2.3 million kilometers (1.4 million miles) from Enceladus. The image scale is 14 kilometers (9 miles) per pixel on 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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07619" onclick="window.open(this.href); return false;" title="Voir l'image PIA07619: Iceball Among Snowballs sur le site de la NASA">Voir l'image PIA07619: Iceball Among Snowballs sur le site de la NASA.</a></div>
PIA07619: Iceball Among Snowballs
<h1>PIA07641: Wrinkled Crescent</h1><div class="PIA07641" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>A target of intense interest to Cassini mission scientists is Enceladus, whose wrinkled and frozen crescent is seen here with Saturn's rings. The planet's dark shadow bisects the ringscape.</p><p>The illuminated terrain seen here is on the moon's trailing hemisphere. North on Enceladus is up and rotated 20 degrees to the left. Enceladus is 505 kilometers (314 miles) across.</p><p>The image was taken in visible green light with the Cassini narrow-angle camera on Oct. 13, 2005 at a distance of approximately 1.2 million kilometers (700,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 106 degrees. The image scale is 7 kilometers (4 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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07641" onclick="window.open(this.href); return false;" title="Voir l'image PIA07641: Wrinkled Crescent sur le site de la NASA">Voir l'image PIA07641: Wrinkled Crescent sur le site de la NASA.</a></div>
PIA07641: Wrinkled Crescent
<h1>PIA07694: Youthful Enceladus</h1><div class="PIA07694" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>For Enceladus, wrinkles mean the opposite of old age. This view of a crescent Enceladus shows a transition zone between a wrinkled and presumably younger region of terrain and an older, more heavily cratered region. The moon's geologically active southern polar region is seen at bottom.</p><p>The lit terrain shown here is on the side of Enceladus (505 kilometers, or 314 miles across) that faces away from Saturn. North is up and rotated 20 degrees to the right.</p><p>The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Dec. 24, 2005 at a distance of approximately 108,000 kilometers (67,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 102 degrees. Image scale is 646 meters (2,118 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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07694" onclick="window.open(this.href); return false;" title="Voir l'image PIA07694: Youthful Enceladus sur le site de la NASA">Voir l'image PIA07694: Youthful Enceladus sur le site de la NASA.</a></div>
PIA07694: Youthful Enceladus
<h1>PIA07708: Fresh Features on Enceladus (False color)</h1><div class="PIA07708" lang="en" style="width:772px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>A false color look reveals subtle details on Enceladus that are not visible in natural color views.</p><p>The now-familiar bluish appearance (in false color views) of the southern "tiger stripe" features and other relatively youthful fractures is almost certainly attributable to larger grain sizes of relatively pure ice, compared to most surface materials.</p><p>On the "tiger stripes," this coarse-grained ice is seen in the colored deposits flanking the fractures as well as inside the fractures. On older fractures on other areas of Enceladus, the blue ice mostly occurs on the exposed wall scarps.</p><p>The color difference across the moon's surface (a subtle gradation from upper left to lower right) could indicate broad-scale compositional differences across the moon's surface. It is also possible that the gradation in color is due to differences in the way the brightness of Enceladus changes toward the limb, a characteristic which is highly dependent on wavelength and viewing geometry.</p><p>See <a href="/catalog/PIA07709">PIA07709</a> for a monochrome version of this view.</p><p>Terrain on the trailing hemisphere of Enceladus (505 kilometers, or 314 miles across) is seen here. North is up.</p><p>The view was created by combining images taken using ultraviolet, green and infrared spectral filters, and then was processed to accentuate subtle color differences. The images were taken with the Cassini spacecraft narrow-angle camera on Jan. 17, 2006 at a distance of approximately 153,000 kilometers (95,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 29 degrees. Image scale is 912 meters (2,994 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">http://saturn.jpl.nasa.gov/home/index.cfm</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07708" onclick="window.open(this.href); return false;" title="Voir l'image PIA07708: Fresh Features on Enceladus (False color) sur le site de la NASA">Voir l'image PIA07708: Fresh Features on Enceladus (False color) sur le site de la NASA.</a></div>
PIA07708: Fresh Features on Enceladus (False color)
<h1>PIA07709: Fresh Features on Enceladus (Monochrome)</h1><div class="PIA07709" lang="en" style="width:750px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Wrinkles and cracks have reworked the surface of Enceladus, perhaps due to the influence of tidal stresses. The monochrome view also makes it clear that certain geological provinces on the moon have been altered by the activity, erasing ancient craters, while other places have retained much of the cratering record.</p><p>See <a href="/catalog/PIA07708">PIA07708</a> for a false-color version of this view.</p><p>Terrain on the trailing hemisphere of Enceladus (505 kilometers, or 314 miles across) is seen here. North is up.</p><p>The image was taken using a near infrared spectral filter sensitive to wavelengths of light centered at 752 nanometers. The view was obtained using the Cassini spacecraft narrow-angle camera on Jan. 17, 2006 at a distance of approximately 153,000 kilometers (95,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase angle, of 29 degrees. Image scale is 912 meters (2,994 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">http://saturn.jpl.nasa.gov/home/index.cfm</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07709" onclick="window.open(this.href); return false;" title="Voir l'image PIA07709: Fresh Features on Enceladus (Monochrome) sur le site de la NASA">Voir l'image PIA07709: Fresh Features on Enceladus (Monochrome) sur le site de la NASA.</a></div>
PIA07709: Fresh Features on Enceladus (Monochrome)
<h1>PIA07724: Enceladus to Scale</h1><div class="PIA07724" lang="en" style="width:685px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Saturn's moon Enceladus is only 505 kilometers (314 miles) across, small enough to fit within the length of the United Kingdom, as illustrated here. The intriguing icy moon also could fit comfortably within the states of Arizona or Colorado.</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 was designed, developed and assembled at JPL. </p><p>For more information about the Cassini-Huygens mission visit <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a>. For additional images visit the Cassini imaging team homepage <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07724" onclick="window.open(this.href); return false;" title="Voir l'image PIA07724: Enceladus to Scale sur le site de la NASA">Voir l'image PIA07724: Enceladus to Scale sur le site de la NASA.</a></div>
PIA07724: Enceladus to Scale
<h1>PIA07758: Fountains of Enceladus</h1><div class="PIA07758" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Recent Cassini images of Saturn's moon Enceladus backlit by the sun show the fountain-like sources of the fine spray of material that towers over the south polar region. This image was taken looking more or less broadside at the "tiger stripe" fractures observed in earlier Enceladus images. It shows discrete plumes of a variety of apparent sizes above the limb (edge) of the moon. This image was acquired on Nov. 27, 2005.</p><p>Imaging scientists, as reported in the journal Science on March 10, 2006, believe that the jets are geysers erupting from pressurized subsurface reservoirs of liquid water above 273 degrees Kelvin (0 degrees Celsius).</p><p>This caption was updated on March 9, 2006.</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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07758" onclick="window.open(this.href); return false;" title="Voir l'image PIA07758: Fountains of Enceladus sur le site de la NASA">Voir l'image PIA07758: Fountains of Enceladus sur le site de la NASA.</a></div>
PIA07758: Fountains of Enceladus
<h1>PIA07759: Fountains of Enceladus - Image #2</h1><div class="PIA07759" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Recent Cassini images of Saturn's moon Enceladus backlit by the sun show the fountain-like sources of the fine spray of material that towers over the south polar region. The image was taken looking more or less broadside at the "tiger stripe" fractures observed in earlier Enceladus images. It shows discrete plumes of a variety of apparent sizes above the limb of the moon.</p><p>The greatly enhanced and colorized image shows the enormous extent of the fainter, larger-scale component of the plume.</p><p>Imaging scientists, as reported in the journal Science on March 10, 2006, believe that the jets are geysers erupting from pressurized subsurface reservoirs of liquid water above 273 degrees Kelvin (0 degrees Celsius).</p><p>This caption was updated on March 9, 2006.</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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07759" onclick="window.open(this.href); return false;" title="Voir l'image PIA07759: Fountains of Enceladus - Image #2 sur le site de la NASA">Voir l'image PIA07759: Fountains of Enceladus - Image #2 sur le site de la NASA.</a></div>
PIA07759: Fountains of Enceladus - Image #2
<h1>PIA07760: Spray Above Enceladus</h1><div class="PIA07760" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>A fine spray of small, icy particles emanating from the warm, geologically unique province surrounding the south pole of Saturn’s moon Enceladus was observed in a Cassini narrow-angle camera image of the crescent moon taken on Jan. 16, 2005.</p><p>Taken from a high-phase angle of 148 degrees -- a viewing geometry in which small particles become much easier to see -- the plume of material becomes more apparent in images processed to enhance faint signals. </p><p>Imaging scientists have measured the light scattered by the plume's particles to determine their abundance and fall-off with height. Though the measurements of particle abundance are more certain within 100 kilometers (60 miles) of the surface, the values measured there are roughly consistent with the abundance of water ice particles measured by other Cassini instruments (reported in September, 2005) at altitudes as high as 400 kilometers (250 miles) above the surface.</p><p>Imaging scientists, as reported in the journal Science on March 10, 2006, believe that the jets are geysers erupting from pressurized subsurface reservoirs of liquid water above 273 degrees Kelvin (0 degrees Celsius). </p><p>The image at the left was taken in visible green light. A dark mask was applied to the moon's bright limb in order to make the plume feature easier to see.</p><p>The image at the right has been color-coded to make faint signals in the plume more apparent. Images of other satellites (such as Tethys and Mimas) taken in the last 10 months from similar lighting and viewing geometries, and with identical camera parameters as this one, were closely examined to demonstrate that the plume towering above Enceladus' south pole is real and not a camera artifact.</p><p>The images were acquired at a distance of about 209,400 kilometers (130,100 miles) from Enceladus. Image scale is about 1 kilometer (0.6 mile) per pixel.</p><p>This caption was updated on March 9, 2006. </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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07760" onclick="window.open(this.href); return false;" title="Voir l'image PIA07760: Spray Above Enceladus sur le site de la NASA">Voir l'image PIA07760: Spray Above Enceladus sur le site de la NASA.</a></div>
PIA07760: Spray Above Enceladus
<h1>PIA07762: Enceladus Plume Movie</h1><div class="PIA07762" lang="en" style="width:501px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Jets of icy particles burst from Saturn’s moon Enceladus in this brief movie sequence of four images taken on Nov. 27, 2005. The sensational discovery of active eruptions on a third outer solar system body (Io and Triton are the others) is surely one of the great highlights of the Cassini mission.</p><p>Imaging scientists, as reported in the journal Science on March 10, 2006, believe that the jets are geysers erupting from pressurized subsurface reservoirs of liquid water above 273 degrees Kelvin (0 degrees Celsius).</p><p>Images taken in January 2005 appeared to show the plume emanating from the fractured south polar region of Enceladus, but the visible plume was only slightly brighter than the background noise in the image, because the lighting geometry was not suitable to reveal the true details of the feature. This potential sighting, in addition to the detection of the icy particles in the plume by other Cassini instruments, prompted imaging scientists to target Enceladus again with exposures designed to confirm the validity of the earlier plume sighting.</p><p>The new views show individual jets, or plume sources, that contribute to the plume with much greater visibility than the earlier images. The full plume towers over the 505-kilometer-wide (314-mile) moon and is at least as tall as the moon's diameter.</p><p>The four 10-second exposures were taken over the course of about 36 minutes at approximately 12 minute intervals.</p><p>Enceladus rotates about 7.5 degrees in longitude over the course of the frames, and most of the observed changes in the appearances of the jets is likely attributable to changes in the viewing geometry. However, some of the changes may be due to actual variation in the flow from the jets on a time scale of tens of minutes.</p><p>Additionally, the shift of the sources seen here should provide information about their location in front of and behind the visible limb (edge) of Enceladus.</p><p>These images were obtained using the Cassini spacecraft narrow-angle camera at distances between 144,350 and 149,520 kilometers (89,695 and 92,907 miles) from Enceladus and at a phase angle of about 161 degrees. Image scale is about 900 meters (2,950 feet) per pixel on Enceladus.</p><p>This caption was updated on March 9, 2006. </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">http://saturn.jpl.nasa.gov</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07762" onclick="window.open(this.href); return false;" title="Voir l'image PIA07762: Enceladus Plume Movie sur le site de la NASA">Voir l'image PIA07762: Enceladus Plume Movie sur le site de la NASA.</a></div>
PIA07762: Enceladus Plume Movie
<h1>PIA07793: Searching for Warmth</h1><div class="PIA07793" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The exciting mystery of an active south polar region on Saturn's icy moon Enceladus continues to unfold as scientists make the correlation between geologically youthful surface fractures and unusually warm temperatures.</p><p>This view shows excess heat radiation from cracks near the moon's south pole. These warm fissures are the source of plumes of dust and gas seen by multiple instruments on the Cassini spacecraft during its flyby of Enceladus on July 14, 2005, as described in a series of papers in the March 10, 2006, issue of the journal Science.</p><p>This image shows two arrays of temperature readings across the surface of Enceladus, as measured by the Cassini composite infrared spectrometer, superimposed on images of the surface taken simultaneously by the imaging science subsystem.</p><p>Surface temperatures in Kelvin, derived from the intensity of infrared radiation detected by the composite infrared spectrometer, are shown along with their formal uncertainties, although true uncertainties for temperatures below about 75 Kelvin (minus 325 degrees Fahrenheit) are not easily described by a single number.</p><p>Enhanced thermal emission is seen in the vicinity of the prominent "tiger stripe" fissures discovered by the imaging cameras. In this image, the excess emission is most strongly seen in the left-most composite infrared spectrometer field of view, which includes a fissure near the end of one of the tiger stripes. The peak temperatures, 86 Kelvin and 90 Kelvin (minus 305 and minus 298 degrees Fahrenheit) respectively, are averages over the composite infrared spectrometer field of view, and other composite infrared spectrometer data suggest that much higher temperatures, up to at least 145 Kelvin (minus 199 degrees Fahrenheit), occur in narrow zones a few hundred meters wide along the tiger stripe fissures. See <a href="/catalog/PIA07794">PIA07794</a> for a related image.</p><p>This image is centered near longitude 135 west, latitude 65 south, and each square from the composite infrared spectrometer field of view is 17.5 kilometers (10.9 miles) across. </p><p>This Cassini narrow-angle camera image has been cropped and resized for presentation.</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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. 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">http://saturn.jpl.nasa.gov</a>. The composite infrared spectrometer team homepage is <a href="http://cirs.gsfc.nasa.gov/">http://cirs.gsfc.nasa.gov/</a>. The imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a></p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07793" onclick="window.open(this.href); return false;" title="Voir l'image PIA07793: Searching for Warmth sur le site de la NASA">Voir l'image PIA07793: Searching for Warmth sur le site de la NASA.</a></div>
PIA07793: Searching for Warmth
<h1>PIA07794: Searching for Warmth</h1><div class="PIA07794" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The exciting mystery of an active south polar region on Saturn's icy moon Enceladus continues to unfold as scientists make the correlation between geologically youthful surface fractures and unusually warm temperatures.</p><p>This view shows excess heat radiation from cracks near the moon's south pole. These warm fissures are the source of plumes of dust and gas seen by multiple instruments on the Cassini spacecraft during its flyby of Enceladus on July 14, 2005, as described in a series of papers in the March 10, 2006, issue of the journal Science.</p><p>This image shows two arrays of temperature readings across the surface of Enceladus, as measured by the Cassini composite infrared spectrometer, superimposed on images of the surface taken simultaneously by the imaging science subsystem.</p><p>Surface temperatures in Kelvin, derived from the intensity of infrared radiation detected by composite infrared spectrometer, are shown along with their formal uncertainties, although true uncertainties for temperatures below about 75 Kelvin (minus 325 degrees Fahrenheit) are not easily described by a single number.</p><p>Enhanced thermal emission is seen in the vicinity of the prominent "tiger stripe" fissures discovered by the imaging cameras. In this image, the excess emission is near the center of the composite infrared spectrometer array, directly over a tiger stripe fissure. The peak temperatures, 86 Kelvin and 90 Kelvin (minus 305 and minus 298 degrees Fahrenheit) respectively, are averages over the composite infrared spectrometer field of view, and other composite and infrared spectrometer data suggest that much higher temperatures, up to at least 145 Kelvin (minus 199 degrees Fahrenheit), occur in narrow zones a few hundred meters wide along the tiger stripe fissures. See <a href="/catalog/PIA07793">PIA07793</a> for a related image.</p><p>This image was taken nearly three times closer to the moon and is centered near longitude 120 west, latitude 82 south, and each composite infrared spectrometer field of view is 6.0 kilometers (3.7 miles) across.</p><p>This Cassini narrow-angle camera image was cropped and resized for presentation. </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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. 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">http://saturn.jpl.nasa.gov</a>. The composite infrared spectrometer team homepage is <a href="http://cirs.gsfc.nasa.gov/">http://cirs.gsfc.nasa.gov/</a>. The imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a></p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07794" onclick="window.open(this.href); return false;" title="Voir l'image PIA07794: Searching for Warmth sur le site de la NASA">Voir l'image PIA07794: Searching for Warmth sur le site de la NASA.</a></div>
PIA07794: Searching for Warmth
<h1>PIA07800: Enceladus the Storyteller</h1><div class="PIA07800" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>A masterpiece of deep time and wrenching gravity, the tortured surface of Saturn's moon Enceladus and its fascinating ongoing geologic activity tell the story of the ancient and present struggles of one tiny world. This is a story that is recounted by imaging scientists in a paper published in the journal Science on March 10, 2006.</p><p>The enhanced color view of Enceladus seen here is largely of the southern hemisphere and includes the south polar terrain at the bottom of the image. </p><p>Ancient craters remain somewhat pristine in some locales, but have clearly relaxed in others. Northward-trending fractures, likely caused by a change in the moon's rate of rotation and the consequent flattening of the moon's shape, rip across the southern hemisphere. The south polar terrain is marked by a striking set of `blue' fractures and encircled by a conspicuous and continuous chain of folds and ridges, testament to the forces within Enceladus that have yet to be silenced.</p><p>The mosaic was created from 21 false-color frames taken during the Cassini spacecraft's close approaches to Enceladus on March 9 and July 14, 2005. Images taken using filters sensitive to ultraviolet, visible and infrared light (spanning wavelengths from 338 to 930 nanometers) were combined to create the individual frames.<p>The mosaic is an orthographic projection centered at 46.8 degrees south latitude, 188 degrees west longitude, and has an image scale of 67 meters (220 feet) per pixel. The original images ranged in resolution from 67 meters per pixel to 350 meters (1,150 feet) per pixel and were taken at distances ranging from 11,100 to 61,300 kilometers (6,900 to 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">http://saturn.jpl.nasa.gov/home/index.cfm</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07800" onclick="window.open(this.href); return false;" title="Voir l'image PIA07800: Enceladus the Storyteller sur le site de la NASA">Voir l'image PIA07800: Enceladus the Storyteller sur le site de la NASA.</a></div>
PIA07800: Enceladus the Storyteller
<h1>PIA07801: Spray Above Enceladus II</h1><div class="PIA07801" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Plumes of icy material extend above the southern polar region of Saturn's moon Enceladus, as imaged by the Cassini spacecraft in January 2005. The monochrome view is presented along with a color-coded image on the right. The view in this image is perpendicular to the tiger stripe fractures that straddle the south pole. Another plume view, <a href="/catalog/PIA07798">PIA07798</a>, was taken one month later and looks along the tiger stripe fractures. See <a href="/catalog/PIA06247">PIA06247</a> for a view of the tiger stripe features.</p><p>Images like these are being analyzed by scientists as they seek to explain the processes that could be producing such incredible features. As reported in the journal Science on March 10, 2006, imaging scientists believe that the plumes are geysers erupting from pressurized subsurface reservoirs of liquid water above 273 degrees Kelvin (0 degrees Celsius).</p><p>These images were taken with the Cassini spacecraft narrow-angle camera at a distance of approximately 209,400 kilometers (130,100 miles) from Enceladus at a Sun-Enceladus-spacecraft, or phase, angle of 148 degrees. The image scale is about 1.3 kilometer (0.8 mile) per pixel.</p><p>A slightly different version of this image product was released in Nov. 2005. See <a href="/catalog/PIA07760">PIA07760</a>.</p><p>The mosaic is an orthographic projection centered at 46.8 degrees south latitude, 188 degrees west longitude, and has an image scale of 67 meters (220 feet) per pixel. The original images ranged in resolution from 67 meters per pixel to 350 meters (1,150 feet) per pixel and were taken at distances ranging from 11,100 to 61,300 kilometers (6,900 to 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">http://saturn.jpl.nasa.gov/</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA07801" onclick="window.open(this.href); return false;" title="Voir l'image PIA07801: Spray Above Enceladus II sur le site de la NASA">Voir l'image PIA07801: Spray Above Enceladus II sur le site de la NASA.</a></div>
PIA07801: Spray Above Enceladus II
<h1>PIA08128: A Pearl at Dusk</h1><div class="PIA08128" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"></p>Enceladus hangs like a single bright pearl against the golden-brown canvas of Saturn and its icy rings. Visible on Saturn is the region where daylight gives way to dusk. Above, the rings throw thin shadows onto the planet.</p><p>Icy Enceladus is 505 kilometers (314 miles) across.</p><p>Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were taken using the Cassini spacecraft wide-angle camera on Jan. 17, 2006 at a distance of approximately 200,000 kilometers (100,000 miles) from Enceladus. The image scale is 10 kilometers (6 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">http://saturn.jpl.nasa.gov/home/index.cfm</a>. The Cassini imaging team homepage is at <a href="http://ciclops.org">http://ciclops.org</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA08128" onclick="window.open(this.href); return false;" title="Voir l'image PIA08128: A Pearl at Dusk sur le site de la NASA">Voir l'image PIA08128: A Pearl at Dusk sur le site de la NASA.</a></div>
PIA08128: A Pearl at Dusk
<h1>PIA08163: The Enceladus Ring</h1><div class="PIA08163" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p><a href="/figures/PIA08163_fig1.jpg"></a><br />The Enceladus Ring (labeled)</p><p>This excellent view of the faint E ring -- a ring feature now known to be created by Enceladus -- also shows two of Saturn's small moons that orbit within the ring, among a field of stars in the background.</p><p>The E ring extends from three to eight Saturn radii -- about 180,000 kilometers (118,000 miles) to 482,000 kilometers (300,000 miles). Its full extent is not visible in this view.</p><p>Calypso (22 kilometers, or 14 miles across) and Helene (32 kilometers, or 20 miles across) orbit within the E ring's expanse. Helene skirts the outer parts of the E ring, but here it is projected in front of a region deeper within the ring.</p><p>Calypso and Helene are trojan satellites, or moons that orbit 60 degrees in front or behind a larger moon. Calypso is a Tethys trojan and Helene is a trojan of Dione.</p><p>An interesting feature of note in this image is the double-banded appearance of the E-ring, which is created because the ring is somewhat fainter in the ringplane than it is 500-1,000 kilometers (300-600 miles) above and below the ringplane. This appearance implies that the particles in this part of the ring have nonzero inclinations (a similar affect is seen in Jupiter's gossamer ring). An object with a nonzero inclination does not orbit exactly at Saturn's ringplane. Instead, its orbit takes it above and below the ringplane. Scientists are not entirely sure why the particles should have such inclinations, but they are fairly certain that the reason involves Enceladus.</p><p>One possible explanation is that all the E ring particles come from the plume of icy material that is shooting due south out of the moon's pole. This means all of the particles are created with a certain velocity out of the ringplane, and then they orbit above and below that plane.</p><p>Another possible explanation is that Enceladus produces particles with a range of speeds, but the moon gravitationally scatters any particles that lie very close to the ringplane, giving them nonzero inclinations.</p><p>Stray light within the camera system is responsible for the broad, faint "Y" shape across the image.</p><p>The image was taken in visible light with the Cassini spacecraft wide-angle camera on March 15, 2006, at a distance of approximately 2.4 million kilometers (1.5 million miles) from Saturn. The image scale on the sky at the distance of Saturn is 142 kilometers (88 miles) per pixel.</p><p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA08163" onclick="window.open(this.href); return false;" title="Voir l'image PIA08163: The Enceladus Ring sur le site de la NASA">Voir l'image PIA08163: The Enceladus Ring sur le site de la NASA.</a></div>
PIA08163: The Enceladus Ring