Galerie de photos des anneaux de la planète Saturne

<h1>PIA02285: Saturn's shadow upon the rings</h1><div class="PIA02285" lang="en" style="width:513px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">Voyager 2 returned this wide-angle, clear-filtered image of the shadow of Saturn upon the rings just after engineers at the Jet Propulsion Laboratory successfully commanded the camera platform to point to the planet. Problems with the platform had prevented the spacecraft from returning photographs the past few days. This first picture after the repair was obtained the evening of Aug. 28, when Voyager 2 was 3.2 million kilometers (2 million miles) from the planet and racing away at more than 26,000 mph. Saturn's nightside can be seen at upper left, with the shadow cast by the planet falling across the rings in the center of this image. The white lines, or "noise," across the photograph are the result of temporary ground communications troubles between the Australian Deep Space Network tracking station and Voyager mission control in Pasadena. The picture was received in Australia in perfect condition; the noise will be removed in subsequent processing. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02285" onclick="window.open(this.href); return false;" title="Voir l'image PIA02285: Saturn's shadow upon the rings sur le site de la NASA">Voir l'image PIA02285: Saturn's shadow upon the rings sur le site de la NASA.</a></div>
PIA02285: Saturn's shadow upon the rings
<h1>PIA02289: Saturn's B rings</h1><div class="PIA02289" lang="en" style="width:183px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">This narrow-angle camera image of Saturn's B Ring and Cassini Division was taken through the Clear filter from a distance of 12.6 million km on 3 November 1980. The Cassini Division separating the A and B Rings is clearly not an empty region. The Division shows several substantial well-defined ringlets. JPL managed the Voyager Project for NASA's Office of Space Science.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02289" onclick="window.open(this.href); return false;" title="Voir l'image PIA02289: Saturn's B rings sur le site de la NASA">Voir l'image PIA02289: Saturn's B rings sur le site de la NASA.</a></div>
PIA02289: Saturn's B rings
<h1>PIA02292: Saturn's F-Ring</h1><div class="PIA02292" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">This narrow-angle camera image of Saturn's F Ring was taken through the Clear filter while at a distance of 0.75 million km from Saturn on 12 November 1980. The kinks and braids of this tightly-constrained ring are visible along with the outer edge of the A Ring. JPL managed the Voyager Project for NASA's Office of Space Science.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02292" onclick="window.open(this.href); return false;" title="Voir l'image PIA02292: Saturn's F-Ring sur le site de la NASA">Voir l'image PIA02292: Saturn's F-Ring sur le site de la NASA.</a></div>
PIA02292: Saturn's F-Ring
<h1>PIA02293: Saturn's F-Ring</h1><div class="PIA02293" lang="en" style="width:270px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">This narrow-angle camera image of Saturn's F Ring was taken through the Clear filter while at a distance of 6.9 million km from Saturn on 8 November 1980. The brightness variations of this tightly-constrained ring shown here indicate that the ring is less uniform in makeup than the larger rings. JPL managed the Voyager Project for NASA's Office of Space Science<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02293" onclick="window.open(this.href); return false;" title="Voir l'image PIA02293: Saturn's F-Ring sur le site de la NASA">Voir l'image PIA02293: Saturn's F-Ring sur le site de la NASA.</a></div>
PIA02293: Saturn's F-Ring
<h1>PIA03550: Saturn's Rings (Artist's Concept)</h1><div class="PIA03550" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This is an artist's concept of Saturn's rings and major icy moons. </p><p>Saturn's rings make up an enormous, complex structure. From edge-to-edge, the ring system would not even fit in the distance between Earth and the Moon. The seven main rings are labeled in the order in which they were discovered. From the planet outward, they are D, C, B, A, F, G and E. </p><p>The D ring is very faint and closest to Saturn. The main rings are A, B and C. The outermost ring, easily seen with Earth-based telescopes, is the A ring. The Cassini Division is the largest gap in the rings and separates the B ring from the A ring. Just outside the A ring is the narrow F ring, shepherded by tiny moons, Pandora and Prometheus. Beyond that are two much fainter rings named G and E. Saturn's diffuse E ring is the largest planetary ring in our solar system, extending from Mimas' orbit to Titan's orbit, about 1 million kilometers (621,370 miles). </p><p>The particles in Saturn's rings are composed primarily of water ice and range in size from microns to tens of meters. The rings show a tremendous amount of structure on all scales; some of this structure is related to gravitational interactions with Saturn's many moons, but much of it remains unexplained. One moonlet, Pan, actually orbits inside the A ring in a 330-kilometer-wide (200-mile) gap called the Encke Gap. The main rings (A, B and C) are less than 100 meters (300 feet) thick in most places, compared to their radial extent of 62,120 kilometers (38,600 miles). The main rings are much younger than the age of the solar system, perhaps only a few hundred million years old. They may have formed from the breakup of one of Saturn's moons or from a comet or meteor that was torn apart by Saturn's gravity.</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://www.nasa.gov/cassini">http://www.nasa.gov/cassini</a> and <a href="http://saturn.jpl.nasa.gov">http://saturn.jpl.nasa.gov</a>. </p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA03550" onclick="window.open(this.href); return false;" title="Voir l'image PIA03550: Saturn's Rings (Artist's Concept) sur le site de la NASA">Voir l'image PIA03550: Saturn's Rings (Artist's Concept) sur le site de la NASA.</a></div>
PIA03550: Saturn's Rings (Artist's Concept)
<h1>PIA05075: Saturn's A Ring From the Inside Out</h1><div class="PIA05075" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The best view of Saturn's rings in the ultraviolet indicates there is more ice toward the outer part of the rings, than in the inner part, hinting at the origins of the rings and their evolution.</p><p>Images taken during the Cassini spacecraft's orbital insertion on June 30 show compositional variation in the A, B and C rings. From the inside out, the "Cassini Division" in faint red at left is followed by the A ring in its entirety. The Cassini Division at left contains thinner, dirtier rings than the turquoise A ring, indicating a more icy composition. The red band roughly three-fourths of the way outward in the A ring is known as the Encke gap. </p><p>The ring system begins from the inside out with the D, C, B and A rings followed by the F, G and E rings. The red in the image indicates sparser ringlets likely made of "dirty," and possibly smaller, particles than in the icier turquoise ringlets.</p><p>This image was taken with the Ultraviolet Imaging Spectrograph instrument, which is capable of resolving the rings to show features up to 97 kilometers (60 miles) across, roughly 100 times the resolution of ultraviolet data obtained by the Voyager 2 spacecraft. </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 was designed, developed and assembled at JPL. The Ultraviolet Imaging Spectrograph was built at, and the team is based at the University of Colorado, 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 Ultraviolet Imaging Spectrograph team home page, <a href="http://lasp.colorado.edu/cassini/">http://lasp.colorado.edu/cassini/</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA05075" onclick="window.open(this.href); return false;" title="Voir l'image PIA05075: Saturn's A Ring From the Inside Out sur le site de la NASA">Voir l'image PIA05075: Saturn's A Ring From the Inside Out sur le site de la NASA.</a></div>
PIA05075: Saturn's A Ring From the Inside Out
<h1>PIA05076: Saturn's C and B Rings From the Inside Out</h1><div class="PIA05076" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Images taken during the Cassini spacecraft's orbital insertion on June 30 show definite compositional variation within the rings. </p><p>This image shows, from left to right, the outer portion of the C ring and inner portion of the B ring. The B ring begins a little more than halfway across the image. The general pattern is from "dirty" particles indicated by red to cleaner ice particles shown in turquoise in the outer parts of the rings. </p><p>The ring system begins from the inside out with the D, C, B and A rings followed by the F, G and E rings. </p><p>This image was taken with the Ultraviolet Imaging Spectrograph instrument, which is capable of resolving the rings to show features up to 97 kilometers (60 miles) across, roughly 100 times the resolution of ultraviolet data obtained by the Voyager 2 spacecraft. </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 was designed, developed and assembled at JPL. The Ultraviolet Imaging Spectrograph was built at, and the team is based at the University of Colorado, 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 Ultraviolet Imaging Spectrograph team home page, <a href="http://lasp.colorado.edu/cassini/">http://lasp.colorado.edu/cassini/</a>.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA05076" onclick="window.open(this.href); return false;" title="Voir l'image PIA05076: Saturn's C and B Rings From the Inside Out sur le site de la NASA">Voir l'image PIA05076: Saturn's C and B Rings From the Inside Out sur le site de la NASA.</a></div>
PIA05076: Saturn's C and B Rings From the Inside Out
<h1>PIA05382: Clumps in the F Ring</h1><div class="PIA05382" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">Scientists have only a rough idea of the lifetime of clumps in Saturn's rings - a mystery that Cassini may help answer.<p />The latest images taken by the Cassini-Huygens spacecraft show clumps seemingly embedded within Saturn's narrow, outermost F ring. The narrow angle camera took the images on Feb. 23, 2004, from a distance of 62.9 million kilometers (39 million miles). The two images taken nearly two hours apart show these clumps as they revolve about the planet. The small dot at center right in the second image is one of Saturn's small moons, Janus, which is 181 kilometers, (112 miles) across.<p />Like all particles in Saturn's ring system, these clump features orbit the planet in the same direction in which the planet rotates. This direction is clockwise as seen from Cassini's southern vantage point below the ring plane. Two clumps in particular, one of them extended, is visible in the upper part of the F ring in the image on the left, and in the lower part of the ring in the image on the right. Other knot-like irregularities in the ring's brightness are visible in the image on the right.<p />The core of the F ring is about 50 kilometers (31miles) wide, and from Cassini's current distance, is not fully visible. The imaging team enhanced the contrast of the images and magnified them to aid visibility of the F ring and the clump features. The camera took the images with the green filter, which is centered at 568 nanometers. The image scale is 377 kilometers (234 miles) per pixel.<p />NASA's two Voyager spacecraft that flew past Saturn in 1980 and 1981 were the first to see these clumps. The Voyager data suggest that the clumps change very little and can be tracked as they orbit for 30 days or more. No clump survived from the time of the first Voyager flyby to the Voyager 2 flyby nine months later. Scientists are not certain of the cause of these features. Among the theories proposed are meteoroid bombardments and inter-particle collisions in the F ring.<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 mission for NASA's Office of Space Science, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colo.<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>.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA05382" onclick="window.open(this.href); return false;" title="Voir l'image PIA05382: Clumps in the F Ring sur le site de la NASA">Voir l'image PIA05382: Clumps in the F Ring sur le site de la NASA.</a></div>
PIA05382: Clumps in the F Ring
<h1>PIA05387: Prometheus and Pandora</h1><div class="PIA05387" lang="en" style="width:404px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini has sighted Prometheus and Pandora, the two F-ring-shepherding moons whose unpredictable orbits both fascinate scientists and wreak havoc on the F ring.</p><p>Prometheus (102 kilometers, or 63 miles across) is visible left of center in the image, inside the F ring. Pandora (84 kilometers, or 52 miles across) appears above center, outside the ring. The dark shadow cast by the planet stretches more than halfway across the A ring, the outermost main ring. The mottled pattern appearing in the dark regions of the image is 'noise' in the signal recorded by the camera system, which has subsequently been magnified by the image processing.</p><p>The F ring is a narrow, ribbon-like structure, with a width seen in this geometry equivalent to a few kilometers. The two small, irregularly shaped moons exert a gravitational influence on particles that make up the F ring, confining it and possibly leading to the formation of clumps, strands and other structures observed there. Pandora prevents the F ring from spreading outward and Prometheus prevents it from spreading inward. However, their interaction with the ring is complex and not fully understood. The shepherds are also known to be responsible for many of the observed structures in Saturn's A ring.</p><p>The moons, which were discovered in images returned by the Voyager 1 spacecraft in 1980, are in chaotic orbits--their orbits can change unpredictably when the moons get very close to each other. This strange behavior was first noticed in ground-based and Hubble Space Telescope observations in 1995, when the rings were seen nearly edge-on from Earth and the usual glare of the rings was reduced, making the satellites more readily visible than usual. The positions of both satellites at that time were different than expected based on Voyager data.</p><p>One of the goals for the Cassini-Huygens mission is to derive more precise orbits for Prometheus and Pandora. Seeing how their orbits change over the duration of the mission will help to determine their masses, which in turn will help constrain models of their interiors and provide a more complete understanding of their effect on the rings.</p><p>This narrow angle camera image was snapped through the broadband green spectral filter, centered at 568 nanometers, on March 10, 2004, when the spacecraft was 55.5 million kilometers (34.5 million miles) from the planet. Image scale is approximately 333 kilometers (207 miles) per pixel. Contrast has been greatly enhanced, and the image has been magnified to aid visibility of the moons as well as structure in the rings.</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/PIA05387" onclick="window.open(this.href); return false;" title="Voir l'image PIA05387: Prometheus and Pandora sur le site de la NASA">Voir l'image PIA05387: Prometheus and Pandora sur le site de la NASA.</a></div>
PIA05387: Prometheus and Pandora
<h1>PIA05393: Pandora and Prometheus Near F Ring</h1><div class="PIA05393" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Two of Saturn's moons, Prometheus (102 kilometers, or 63 miles across) and Pandora (84 kilometers, or 52 miles across), are seen here shepherding the planet's narrow F-ring. Prometheus overtakes Pandora in orbit around Saturn about every 25 days. Slightly above the pair and to the right is another moon, Epimetheus (116 kilometers, or 72 miles across). The image was taken with the narrow angle camera on the Cassini spacecraft on May 1, 2004, at a distance of 31.4 million kilometers (19.5 million miles) from Saturn. Image scale is 187 kilometers (116 miles) per pixel. The image has been magnified and greatly 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 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/PIA05393" onclick="window.open(this.href); return false;" title="Voir l'image PIA05393: Pandora and Prometheus Near F Ring sur le site de la NASA">Voir l'image PIA05393: Pandora and Prometheus Near F Ring sur le site de la NASA.</a></div>
PIA05393: Pandora and Prometheus Near F Ring
<h1>PIA05396: Groovy Rings and Moons</h1><div class="PIA05396" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The multitude of grooves for which Saturn's rings are famed, clumps in the F ring, and three Saturnian moons are visible in this image. Moons visible in the image are: Mimas (398 kilometers or 247 miles across) above the rings at left; Epimetheus (116 kilometers or 72 miles across) just above the A ring; Enceladus (499 kilometers or 310 miles across) near upper right. The image was taken with the Cassini narrow angle camera on May 10, 2004, at a distance of 27.1 million kilometers (16.8 million miles) from Saturn. Image scale is 162 kilometers (101 miles) per pixel. Contrast in the image was 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 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/PIA05396" onclick="window.open(this.href); return false;" title="Voir l'image PIA05396: Groovy Rings and Moons sur le site de la NASA">Voir l'image PIA05396: Groovy Rings and Moons sur le site de la NASA.</a></div>
PIA05396: Groovy Rings and Moons
<h1>PIA05417: Rings and More Rings</h1><div class="PIA05417" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This dramatic view of Saturn's rings draped by the shadow of Saturn, shows brightness variations that correspond to differences in the concentration of the ring particles as they orbit the planet. </p><p>The planet's western limb is visible in the upper right corner. Three of Saturn's moons can be seen here: Bright Enceladus (499 kilometers, or 310 miles across) is visible near lower right; Epimetheus (116 kilometers, or 72 miles across) appears at center left; and interior to the F ring, near the top of the image, is Prometheus (102 kilometers, or 63 miles across). The F ring, the outermost ring shown here, displays several knot-like features near the left side of the image.</p><p>The image was taken in visible light by the Cassini spacecraft wide angle camera on July 3, 2004, from a distance of 1.5 million kilometers (930,000 miles) from Saturn, at a Sun-Saturn-spacecraft, or phase, angle of about 108 degrees. This is the first processed wide angle camera image to be released since Cassini's encounter with Jupiter in 2000. The image scale is 87 kilometers (54 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/PIA05417" onclick="window.open(this.href); return false;" title="Voir l'image PIA05417: Rings and More Rings sur le site de la NASA">Voir l'image PIA05417: Rings and More Rings sur le site de la NASA.</a></div>
PIA05417: Rings and More Rings
<h1>PIA05421: Ringscape In Color</h1><div class="PIA05421" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Nine days before it entered orbit, Cassini spacecraft captured this exquisite natural color view of Saturn's rings. The images that make up this composition were obtained from Cassini's vantage point beneath the ring plane with the narrow angle camera on June 21, 2004, at a distance of 6.4 million kilometers (4 million miles) from Saturn. The image scale is 38 kilometers (23 miles) per pixel.</p><p>The brightest part of the rings, curving from the upper right to the lower left in the image, is the B ring. Many bands throughout the B ring have a pronounced sandy color. Other color variations across the rings can be seen. Color variations in Saturn's rings have previously been seen in Voyager and Hubble Space Telescope images. Cassini's images show that color variations in the rings are more pronounced in this viewing geometry than they are when seen from Earth. </p><p>Saturn's rings are made primarily of water ice. Since pure water ice is white, it is believed that different colors in the rings reflect different amounts of contamination by other materials such as rock or carbon compounds. In conjunction with information from other Cassini instruments, Cassini images will help scientists determine the composition of different parts of Saturn's ring system.</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/PIA05421" onclick="window.open(this.href); return false;" title="Voir l'image PIA05421: Ringscape In Color sur le site de la NASA">Voir l'image PIA05421: Ringscape In Color sur le site de la NASA.</a></div>
PIA05421: Ringscape In Color
<h1>PIA05424: Light and Shadow</h1><div class="PIA05424" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The dark shadow of Saturn’s southern hemisphere spreads across the planet's rings all the way to the Encke gap. Close inspection of the shadow's left-most extension reveals the penumbra, the blurry region in which ring features are only partially illuminated. A viewer within the penumbra would see the Sun partially eclipsed by Saturn.</p><p>The image was taken with the Cassini spacecraft narrow angle camera on June 21, 2004, from a distance of 6.3 million kilometers (3.9 million miles) from Saturn through a filter sensitive to visible green light. The image scale is 37 kilometers (23 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/PIA05424" onclick="window.open(this.href); return false;" title="Voir l'image PIA05424: Light and Shadow sur le site de la NASA">Voir l'image PIA05424: Light and Shadow sur le site de la NASA.</a></div>
PIA05424: Light and Shadow
<h1>PIA06061: Passage through the Ring Plane</h1><div class="PIA06061" lang="en" style="width:750px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>The path that lies ahead for the Cassini-Huygens mission is indicated in this image which illustrates where the spacecraft will be just 27 days from now, when it arrives at Saturn and crosses the ring plane 33 minutes before performing its critical orbital insertion maneuver.</p><p>The X indicates the point where Cassini will pierce the ring plane on June 30, 2004, going from south to north of the ring plane, 33 minutes before the main engine fires to begin orbital insertion. The indicated point is between the narrow F-ring on the left and Saturn's tenuous G-ring which is too faint to be seen in this exposure.</p><p>The image was taken on May 11, 2004 when the spacecraft was 26.3 million kilometers (16.3 million miles) from Saturn. Image scale is 158 kilometers (98 miles) per pixel. Moons visible in this image: Janus (181 kilometers or 113 miles across), one of the co-orbital moons; Pandora (84 kilometers or 52 miles across), one of the F ring shepherding moons; and Enceladus (499 kilometers or 310 miles across), a moon which may be heated from within and thus have a liquid sub-surface ocean.</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/PIA06061" onclick="window.open(this.href); return false;" title="Voir l'image PIA06061: Passage through the Ring Plane sur le site de la NASA">Voir l'image PIA06061: Passage through the Ring Plane sur le site de la NASA.</a></div>
PIA06061: Passage through the Ring Plane
<h1>PIA06092: Cassini Captures the Cassini Division</h1><div class="PIA06092" lang="en" style="width:768px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image shows the region of Saturn's rings known as the Cassini Division. It was taken by the narrow angle camera on the Cassini spacecraft after successful entry into Saturn's orbit. The view shows the dark, or unlit, side of the rings. </p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06092" onclick="window.open(this.href); return false;" title="Voir l'image PIA06092: Cassini Captures the Cassini Division sur le site de la NASA">Voir l'image PIA06092: Cassini Captures the Cassini Division sur le site de la NASA.</a></div>
PIA06092: Cassini Captures the Cassini Division
<h1>PIA06093: Two Waves in One Spectacular Image of Saturn's Rings</h1><div class="PIA06093" lang="en" style="width:768px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image shows a bending wave (right) and density wave in Saturn's A ring, interior to the Encke Gap. It was taken by the narrow angle camera on the Cassini spacecraft after successful entry into Saturn's orbit. The view shows the dark, or unlit, side of the rings. </p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06093" onclick="window.open(this.href); return false;" title="Voir l'image PIA06093: Two Waves in One Spectacular Image of Saturn's Rings sur le site de la NASA">Voir l'image PIA06093: Two Waves in One Spectacular Image of Saturn's Rings sur le site de la NASA.</a></div>
PIA06093: Two Waves in One Spectacular Image of Saturn's Rings
<h1>PIA06094: Rippling Rings</h1><div class="PIA06094" lang="en" style="width:768px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This is one of the first images taken by the Cassini spacecraft after it successfully entered Saturn's orbit. It was taken by the spacecraft's narrow angle camera.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06094" onclick="window.open(this.href); return false;" title="Voir l'image PIA06094: Rippling Rings sur le site de la NASA">Voir l'image PIA06094: Rippling Rings sur le site de la NASA.</a></div>
PIA06094: Rippling Rings
<h1>PIA06095: Rings Full of Waves</h1><div class="PIA06095" lang="en" style="width:768px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image shows three density waves in Saturn's A ring. It was taken by the narrow angle camera on the Cassini spacecraft after successful entry into Saturn's orbit. The view shows the dark, or unlit, side of the rings. </p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06095" onclick="window.open(this.href); return false;" title="Voir l'image PIA06095: Rings Full of Waves sur le site de la NASA">Voir l'image PIA06095: Rings Full of Waves sur le site de la NASA.</a></div>
PIA06095: Rings Full of Waves
<h1>PIA06096: Rings Full of Waves (zoom)</h1><div class="PIA06096" lang="en" style="width:726px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image shows a close-up view of a density wave in Saturn's A ring. It was taken by the narrow angle camera on the Cassini spacecraft after successful entry into Saturn's orbit. The view shows the dark, or unlit, side of the rings. </p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06096" onclick="window.open(this.href); return false;" title="Voir l'image PIA06096: Rings Full of Waves (zoom) sur le site de la NASA">Voir l'image PIA06096: Rings Full of Waves (zoom) sur le site de la NASA.</a></div>
PIA06096: Rings Full of Waves (zoom)
<h1>PIA06097: Cassini's First Picture of F Ring</h1><div class="PIA06097" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This is one of the first images taken of Saturn's F ring by the Cassini spacecraft after it successfully entered Saturn's orbit. It was taken by the spacecraft's narrow angle camera and shows the sunlit side of the rings.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06097" onclick="window.open(this.href); return false;" title="Voir l'image PIA06097: Cassini's First Picture of F Ring sur le site de la NASA">Voir l'image PIA06097: Cassini's First Picture of F Ring sur le site de la NASA.</a></div>
PIA06097: Cassini's First Picture of F Ring
<h1>PIA06098: Wide View of Saturn's F Ring</h1><div class="PIA06098" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This is one of the first images taken of Saturn's F ring by the Cassini spacecraft after it successfully entered Saturn's orbit. It was taken by the spacecraft's wide angle camera and shows the sunlit side of the rings.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06098" onclick="window.open(this.href); return false;" title="Voir l'image PIA06098: Wide View of Saturn's F Ring sur le site de la NASA">Voir l'image PIA06098: Wide View of Saturn's F Ring sur le site de la NASA.</a></div>
PIA06098: Wide View of Saturn's F Ring
<h1>PIA06099: The Encke Gap as Never Seen Before</h1><div class="PIA06099" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>This image shows in superb detail the region in Saturn's rings known as the Encke Gap. It was taken by the narrow angle camera on the Cassini spacecraft after successful entry into Saturn's orbit. The view shows the sunlit side of the rings.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA06099" onclick="window.open(this.href); return false;" title="Voir l'image PIA06099: The Encke Gap as Never Seen Before sur le site de la NASA">Voir l'image PIA06099: The Encke Gap as Never Seen Before sur le site de la NASA.</a></div>
PIA06099: The Encke Gap as Never Seen Before
<h1>PIA06144: Tilt and Whirl</h1><div class="PIA06144" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Zigzagging kinks and knots dance around Saturn in this movie of the F ring from Cassini. From a great distance, as during Cassini's initial approach to Saturn in mid-2004, the F ring appears as a faint, knotted strand of material at the outer fringe of Saturn's immense ring system. From this close vantage point, just after the spacecraft rounded the planet to begin its second orbit, the F ring resolves into several ringlets with a bright central core. The core of the F ring is about 50 kilometers (31 miles) wide and is located at a distance of approximately 80,100 kilometers (49,800 miles) from Saturn's cloud tops.</p><p>Scientists have only a rough idea of the lifetime of features like knots and clumps in Saturn's rings, and studies of images, such as those comprising this movie, will help them piece together this story.</p><p>The view here is from Cassini's southern vantage point, below the ringplane. During the course of the movie sequence, Cassini was headed on a trajectory that took the spacecraft away from the planet and farther south, so that the rings appear to tilt farther upward. To help visualize this, note that the top portion of the F ring is closer to the spacecraft, while the bottom portion is farther away and curves around the far side of Saturn.The movie consists of 44 frames taken three minutes apart, so that the span of time represented in the sequence is almost exactly two hours, or about one-eight of a Saturn rotation. The images that comprise this movie sequence were taken in visible light with the Cassini spacecraft narrow angle camera on Oct. 28, 2004, and at distances ranging from approximately 516,000 kilometers (321,000 miles) to 562,000 kilometers (349,000 miles). No enhancement was performed on the images. </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/PIA06144" onclick="window.open(this.href); return false;" title="Voir l'image PIA06144: Tilt and Whirl sur le site de la NASA">Voir l'image PIA06144: Tilt and Whirl sur le site de la NASA.</a></div>
PIA06144: Tilt and Whirl
<h1>PIA06175: Panoramic Rings</h1><div class="PIA06175" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Saturn's most prominent feature, its dazzling ring system, takes center stage in this stunning natural color mosaic which reveals the color and diversity present in this wonder of the solar system. Gaps, gravitational resonances and wave patterns are all present, and the delicate color variations across the system are clearly visible.</p><p>This mosaic of six images covers a distance of approximately 62,000 kilometers along the ring plane, from a radius of 74,565 kilometers to 136,780 kilometers (46,333 to 84,991 miles) from the planet's center.</p><p>This view is from Cassini's vantage point beneath the ring plane. The rings are tilted away from Cassini at an angle of about 4 degrees.</p><p>Images taken using red, green and blue spectral filters were used to create this natural color mosaic. The images were acquired using the Cassini spacecraft narrow angle camera on Dec. 12, 2004, at a distance of approximately 1.8 million kilometers (1.1 million miles). The image scale is 10.5 kilometers (6.5 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/PIA06175" onclick="window.open(this.href); return false;" title="Voir l'image PIA06175: Panoramic Rings sur le site de la NASA">Voir l'image PIA06175: Panoramic Rings sur le site de la NASA.</a></div>
PIA06175: Panoramic Rings
<h1>PIA06195: New Ring Phenomena</h1><div class="PIA06195" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>A collection of new ring phenomena, first observed in the sequence of images taken of the dark side of Saturn's rings immediately after Cassini entered orbit, may be evidence of the clumping and aggregation of ring particles. This phenomena is caused by the combined gravitational effects of Saturn, orbiting moons, and other ring particles.</p><p>Image A displays an unusual mottled-looking narrow region, with a radial width varying with longitude from 5 to 10 kilometers (3 to 6 miles), seen for the first time about 60 kilometers (37 miles) inside the outer edge of Saturn's A ring. The resolution of this dayside image is about 1 kilometer (0.6 miles) per pixel. Image B is a close-up of the region, mapped into a longitude-radius system and contrast enhanced. The region is characterized by blotchy light and dark areas about 30 to 40 kilometers (19 to 25 miles) in longitudinal extent. The observed longitudinal extent of this region is about 3.5 degrees.</p><p>The mottled regions also are probably caused by particle clumping brought about by gravitational disturbances. The outer A ring edge is sculpted into a seven-lobed pattern called a Lindblad resonance (a type of dynamical resonance that occurs in rings systems) with the co-orbital satellites Janus and Epimetheus. The resonant perturbations in this region are complicated by the presence of these two moons whose orbits are within 50 kilometers (31 miles) of each other. </p><p>Image C is a dark-side image of the outer edge of the Encke gap, with a resolution of about 270 meters (886 feet) pixel, taken 18 degrees upstream from the moon Pan, which inhabits the gap. The regularly spaced, narrow dark lanes observed here are the wakes caused by Pan. Rope-like features can be seen between the first two wakes nearest the gap edge. These features are unique in all Cassini images taken so far. They generally are between 10 and 20 kilometers (6 and 12 miles) long.</p><p>In their orbits around Saturn, the particles comprising the rings in this region pass through the Pan wakes. When they do so, they are forced closer together than usual. These ropy features appear to be a product of the enhanced gravitational disturbances that occur when the particles pass through the wakes caused by Pan and consequently are squeezed close together. These disturbances obviously persist even outside the wakes, as is evident here in the presence of the ropy structures in the bands in between the wakes.</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/PIA06195" onclick="window.open(this.href); return false;" title="Voir l'image PIA06195: New Ring Phenomena sur le site de la NASA">Voir l'image PIA06195: New Ring Phenomena sur le site de la NASA.</a></div>
PIA06195: New Ring Phenomena
<h1>PIA06196: Rings and More Rings</h1><div class="PIA06196" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini images have revealed the presence of previously unseen faint rings in some of the gaps in Saturn's rings--possible indicators of small yet-unseen moons.</p><p>Image A is a contrast-stretched view of the 270-kilometer-wide (170 mile) Maxwell gap in Saturn's C ring. The right arrow points to the optically thick Maxwell ringlet; the left arrow points to the new diffuse ring seen inside it.</p><p>Image B is a view of the approximately 350-kilometer-wide (220 miles) Huygens gap, between the outer edge of Saturn's B ring (on the left) and the dark bands (on the right) in the Cassini division. The right arrow points to the optically thick Huygens ring; the left arrow points to the new diffuse ring inside it.</p><p>Image C is a view of the ringlets inside the Encke gap. Some of these had been seen by NASA's Voyager spacecraft, but this contrast-enhanced Cassini lit-side image shows the presence of three major ringlets and a rather tenuous one. </p><p>The center ringlet, which in this image has the highest optical depth among the ringlets, is coincident with Pan's orbit. This finding, along with observed variations in brightness along the ringlet, implies that accumulations of particles in the ringlet are maintained in special orbits that prevent them from colliding with Pan.</p><p>In Image D, which is a composite of several wide angle images taken of the lit-side of the rings after orbit insertion, there is clear indication of material extending about 400 kilometers (250 miles) beyond the edge of Saturn's overexposed A ring (on the right), as well as two diffuse rings: a 300-kilometer-wide (190 mile) ring of material, R/2004 S1, in the orbit of Atlas (left-most arrow) and another ring, R/2004 S2, comparable to the Atlas ring and immediately interior to Prometheus's orbit (right-most arrow). These rings had been reported earlier and are comparable to the jovian ring. Prometheus's orbit is elliptical, and brings the moon as close to Saturn as the outer edge of R/2004 S2 and as far away from the planet as the inner sharp boundary of Saturn's F ring. These observations indicate that Prometheus has swept material from the region occupied by its orbit.</p><p>It is not clear yet whether the origin of all these low-optical depth ringlets is the same. The association of the Atlas ring with Atlas and the main Encke ringlet with Pan would suggest that these rings derive from their associated moon. In other cases, a ring may exist because the material (or small parent bodies within it) are shepherded by a larger moon also present in the gap. The particles in many or all of these diffuse ringlets may have substantial fractions of micrometer-sized dust, implying that non-gravitational forces also may affect the ringlets' dynamics. In any case, the presence of narrow, diffuse ringlets in gaps like Maxwell and Huygens, along with the major Maxwell and Huygens ringlets, and the additional narrow ringlets in the Encke gap, suggests that there may be yet unseen moonlets in these gaps.</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/PIA06196" onclick="window.open(this.href); return false;" title="Voir l'image PIA06196: Rings and More Rings sur le site de la NASA">Voir l'image PIA06196: Rings and More Rings sur le site de la NASA.</a></div>
PIA06196: Rings and More Rings
<h1>PIA06237: Wavemaker Moon</h1><div class="PIA06237" lang="en" style="width:744px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini's confirmation that a small moon orbits within the Keeler gap in Saturn's rings is made all the more exciting by this image, in which the disk of the 7 kilometer-wide body (4-miles) is resolved for the first time.</p><p>The new body, provisionally named S/2005 S1, was first seen in a time-lapse sequence of images taken on May 1, 2005, as Cassini began its climb to higher elevations in orbit around Saturn (see <a href="/catalog/PIA06238">PIA06238</a> for the movie). This view was acquired one day after the discovery sequence of images and has allowed scientists to measure the moon's size and brightness.</p><p>The Keeler gap edges also bear similarities to the scalloped edges ofthe 322-kilometer-wide (200-mile) Encke gap, where Pan resides. From thesize of the waves seen in the Encke gap, imaging scientists were able toestimate the mass of Pan. They expect to do the same eventually with this new moon.</p><p>This image was obtained with the Cassini spacecraft narrow-angle camera on May 2, 2005, at a distance of about 594,000 kilometers (369,000 miles) from Saturn. Cassini was about 525,000 kilometers (326,000 miles) above the ringplane when the image was taken. Resolution in the original image was 3 kilometers (2 miles) per pixel. The image has been magnified by a factor of two, and contrast has been enhanced, to aid visibility of the small moonlet.</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/PIA06237" onclick="window.open(this.href); return false;" title="Voir l'image PIA06237: Wavemaker Moon sur le site de la NASA">Voir l'image PIA06237: Wavemaker Moon sur le site de la NASA.</a></div>
PIA06237: Wavemaker Moon
<h1>PIA06238: Discovery of the Wavemaker (animation)</h1><div class="PIA06238" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini's celestial sleuthing has paid off with this time-lapse series of images which confirmed earlier suspicions that a small moon was orbiting within the narrow Keeler gap of Saturn's rings.</p><p>The movie sequence, which consists of 12 images taken over 16 minutes while Cassini gazed down upon the sunlit side of the A ring, shows a tiny moon orbiting in the center of the Keeler gap, churning up waves in the gap edges as it goes. The pattern of waves travels with the moon in its orbit.</p><p>The Keeler gap is located about 250 kilometers (155 miles) inside the outer edge of the A ring, which is also the outer edge of the bright main rings. The new object is about 7 kilometers across (4 miles) and reflects about 50 percent of the sunlight that falls upon it -- a brightness that is typical of particles in the nearby rings.</p><p>The new body has been provisionally named S/2005 S1.</p><p>Imaging scientists predicted the moon's presence and its orbital distance from Saturn after July 2004, when they saw a set of peculiar spiky and wispy features in the Keeler gap's outer edge. The similarities of the Keeler gap features to those noted in Saturn's F ring and the Encke gap led the scientists to conclude that a small body, a few kilometers across, was lurking in the center of the Keeler gap, awaiting discovery.</p><p>Also included here is a view of the same scene created by combining six individual, unmagnified frames used in the movie sequence. This digital composite view improves the overall resolution of the scene compared to that available in any of the single images.</p><p>The images in this movie sequence were obtained with the Cassini spacecraft narrow-angle camera on May 1, 2005, at a distance of approximately 1.1 million kilometers (708,000 miles) from Saturn. Resolution in the original image was 8 kilometers (5 miles) per pixel. The images in the movie sequence have been magnified in (the vertical direction only) by a factor of two to aid visibility of features caused within the gap by the moonlet.</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/PIA06238" onclick="window.open(this.href); return false;" title="Voir l'image PIA06238: Discovery of the Wavemaker (animation) sur le site de la NASA">Voir l'image PIA06238: Discovery of the Wavemaker (animation) sur le site de la NASA.</a></div>
PIA06238: Discovery of the Wavemaker (animation)
<h1>PIA06239: Discovery of the Wavemaker</h1><div class="PIA06239" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Cassini's celestial sleuthing has paid off with a series of images which confirmed earlier suspicions that a small moon was orbiting within the narrow Keeler gap within Saturn's rings.</p><p>This view was created by combining six individual, unmagnified frames from the movie sequence of images in which the moon was discovered. The digital composite view improves the overall resolution of the scene compared to that available in any of the single images (see <a href="/catalog/PIA06238">PIA06238</a> for the movie sequence).</p><p>The Keeler gap is located about 250 kilometers (155 miles) inside the outer edge of the A ring, which is also the outer edge of the bright main rings. The new object is about 7 kilometers (4 miles) across and reflects about 50 percent of the sunlight light that falls upon it -- a brightness that is typical of particles in the nearby rings.</p><p>The new body has been provisionally named S/2005 S1.</p><p>Imaging scientists predicted the moon's presence and its orbital distance from Saturn after July 2004, when they saw a set of peculiar spiky and wispy features in the Keeler gap's outer edge. The similarities of the Keeler gap features to those noted in Saturn's F ring and the Encke gap led the scientists to conclude that a small body, a few kilometers across, was lurking in the center of the Keeler gap, awaiting discovery.</p><p>Also included here is a view of the same scene created by combining six individual, unmagnified frames used in the movie sequence. This digital composite view improves the overall resolution of the scene compared to that available in any of the single images.</p><p>These images were obtained with the Cassini spacecraft narrow-angle camera on May 1, 2005, at a distance of approximately 1.1 million kilometers (708,000 miles) from Saturn. Resolution in the original image was 8 kilometers (5 miles) per pixel. The images in the movie sequence have been magnified in (the vertical direction only) by a factor of two to aid visibility of features caused within the gap by the moonlet.</p></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/PIA06239" onclick="window.open(this.href); return false;" title="Voir l'image PIA06239: Discovery of the Wavemaker sur le site de la NASA">Voir l'image PIA06239: Discovery of the Wavemaker sur le site de la NASA.</a></div>
PIA06239: Discovery of the Wavemaker