As Prometheus pulls away from an encounter with Saturn's F ring, its immediate effects on the ring material are clear. The moon has pulled toward it a faint streamer of material from the inner, flanking ringlet and even created a modest bulge in the ring's bright core.
Above the moon in this image is the feature created during the previous passage of Prometheus (86 kilometers, or 53 miles across). The older streamer feature has sheared diagonally over the course of an orbit, becoming a dark channel. This too is the fate of the newly created streamer.
This view looks toward the sunlit side of the rings from about 14 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Aug. 6, 2008. The view was obtained at a distance of approximately 1 million kilometers (635,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 32 degrees. Image scale is 6 kilometers (4 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10461: Opening a Channel sur le site de la NASA.
Prometheus draws a fresh streamer of material from the F ring as it passes the ring's interior edge. The streamer will continuously shear out as it orbits the planet, becoming more elongated and increasingly aligned with the F ring with time.
A single large crater is the principle feature visible on Prometheus (102 kilometers, or 63 miles across) in this view. The moon is lit partly by bright sunlight and partly by reflected light from Saturn.
This view looks toward the unlit side of the rings from about 57 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 11, 2007 at a distance of approximately 1.7 million kilometers (1.1 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 130 degrees. Image scale is 10 kilometers (6 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Cassini peers through the icy particles that comprise Saturn's rings as Prometheus sits perched on the planet's limb (edge). The rings cast shadows on the planet, with darker regions corresponding to places where the ring material is denser. The narrow dense regions are created by gravitational resonances with moons, like Prometheus, that orbit near the rings. Prometheus is 102 kilometers (63 miles) across.
The thin, bright core of the F ring can be seen against the planet and above Prometheus.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 3, 2005, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Saturn. The image scale is 13 kilometers (8 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.
Saturn's shepherd moon Prometheus hovers between the A and F rings as if suspended on an invisible thread, while bright clouds drift in Saturn's atmosphere approximately 130,000 kilometers (81,000 miles) beyond. It is noteworthy that such clouds are visible here in the shadows cast by the rings.
Prometheus is 102 kilometers (63 miles) across.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 3, 2005, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Saturn. The image scale is 13 kilometers (8 miles) per pixel. This view was processed to enhance fine details.
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.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.
Prometheus poses here with its latest creation: a dark, diagonal gore in the tenuous material interior to Saturn's F ring. The shepherd moon creates a new gore each time it comes closest to the F ring in its orbit of Saturn, and the memory of previous passes is preserved in the rings's structure for some time afterward. Prometheus is 102 kilometers (63 miles) across.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Aug. 20, 2005, at a distance of approximately 499,000 kilometers (310,000 miles) from Saturn and at a high Sun-Saturn-spacecraft, or phase, angle of 144 degrees. Resolution in the original image was 3 kilometers (2 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.
Saturn's moon Prometheus pulls away from an encounter with the narrow F ring, trailing a streamer of fine, icy particles behind it.
See PIA08397 for a movie of Prometheus creating a streamer in the F ring.
Prometheus (86 kilometers, or 53 miles across at its widest point) is lit by the Sun from lower right. Dim, reflected light from Saturn illuminates the moon from the top. Some hints of topography can be seen on the Saturn-lit side. The F-ring streamer is seen at left.
This view looks toward the unilluminated side of the rings from about 67 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on May 25, 2008. The view was obtained at a distance of approximately 534,000 kilometers (332,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 92 degrees. Image scale is 3 kilometers (2 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10415: Streaming Away sur le site de la NASA.
The ring moon Prometheus continues its work shaping the delicate F ring as Dione looks on. It is easy to see how Prometheus has an irregular, oblong shape, while Dione is quite round.
The rings are partly cut off by Saturn's shadow at right.
Prometheus is 102 kilometers (63 miles) wide; Dione is 1,123 kilometers (700 miles) wide.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Dec. 20, 2005, at a distance of approximately 2.5 million kilometers (1.6 million miles) from Dione and 2.2 million kilometers (1.4 million miles) from Prometheus. The image scale is 15 kilometers (9 miles) per pixel on Dione and 13 kilometers (8 miles) per pixel on Prometheus.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.
The shepherd moon Prometheus is lit partly by reflected light from Saturn as it lurks near the heavily perturbed F ring.
The left side of Prometheus (102 kilometers, or 63 miles across) is overexposed by the blinding Sun, but hints of craters can be seen on the Saturn-lit side.
This view looks toward the unlit side of the rings from about 52 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 16, 2007 at a distance of approximately 1.8 million kilometers (1.1 million miles) from Prometheus. Image scale is 11 kilometers (7 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Prometheus, one of the F ring shepherds, is seen here orbiting between the A and F rings. The F ring shows a kink near Prometheus, due to the moon's gravitational effect.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 15, 2008 at a distance of approximately 959,000 kilometers (596,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 42 degrees. Image scale is 5 kilometers (3 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10520: Prometheus Brings Change to the F Ring sur le site de la NASA.
Saturn's moon Prometheus is seen here emerging from the darkness of Saturn's shadow. Prometheus is 102 kilometers (63 miles) across.
This shepherd moon, like most of Saturn's moons, always keeps the same face pointing toward the planet. An observer on the moon's Saturn-facing side would never see the Sun directly overhead at noon, for the planet would always be in the way (creating an eclipse). Instead, the Sun would rise in the east, but as noon approached the eclipse would begin, bringing darkness a second time. Night comes twice on Prometheus.
This image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 3, 2005, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Saturn. The image scale is 13 kilometers (8 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.
Prometheus draws material from the F ring along an invisible thread of gravity. Near lower left is an identical feature the moon created on a previous pass near the ring.
Prometheus (102 kilometers, or 63 miles across) is overexposed in this image, which was taken as part of a sequence designed to help refine scientists' understanding of the orbits of Saturn's small moons.
This view looks toward the unlit side of the rings from about 41 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 14, 2007 at a distance of approximately 1.8 million kilometers (1.1 million miles) from Prometheus. Image scale is 11 kilometers (7 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Prometheus is caught here casting a shadow on the F ring. To the right, the F ring also shows a gore where Prometheus recently entered into the ring, scattering material out of its way.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 29, 2008 at a distance of approximately 1.167 million kilometers (725,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 28 degrees. Image scale is 7 kilometers (4 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10552: Shadows and Gores sur le site de la NASA.
Saturn's shepherd moon Prometheus reveals its elongated, irregular form to Cassini in this image. The moon's long axis points toward Saturn. Prometheus is 102 kilometers (63 miles) across.
This view shows the southern part of the moon's anti-Saturn side (the face that always points away from Saturn).
The image was taken in visible red light with the Cassini spacecraft narrow-angle camera on June 7, 2005, at a distance of approximately 438,000 kilometers (272,000 miles) from Prometheus. Resolution in the original image was 3 kilometers (2 miles) per pixel. The image has been contrast-enhanced and magnified by a factor of two to aid visibility.
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.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.
A shepherd moon can do more to define ring structures than just keep the flock of particles in line, as Cassini spacecraft images such as this have shown.
Prometheus (102 kilometers, or 63 miles across) is seen here with two long streamers of material that it has pulled out of the F ring. When Prometheus comes close to the F ring in its orbit, the moon's gravity tugs on the ring particles. The disturbed particles, now pulled into orbits slightly closer to Saturn and therefore faster, shear out during successive orbits, creating the long and delicate streamers seen here.
This view looks toward the unlit side of the rings from about 31 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 29, 2006 at a distance of approximately 1.7 million kilometers (1 million miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 160 degrees. Image scale is 10 kilometers (6 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Prometheus tugs icy particles from the F ring into fanciful shapes like ropes of glowing neon.
Although Prometheus (86 kilometers, or 53 miles across) is overexposed here, the moon's irregular outline is quite easy to see.
This view looks toward the sunlit side of the rings from about 7 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 22, 2008. The view was obtained at a distance of approximately 1 million kilometers (652,000 miles) from Saturn. Image scale is 6 kilometers (4 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA09909: The Ringsmith sur le site de la NASA.
Prometheus—lit partly by direct sunlight and partly by saturnshine—pulls at material in the inner portion of the F ring. Saturnshine is sunlight reflected by the Ringed Planet, which often brightens the night sides of Saturn's moons.
This view looks toward irregularly shaped Prometheus (102 kilometers, or 63 miles across at its widest point) and the unilluminated side of the rings from about 41 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 10, 2008. The view was obtained at a distance of approximately 1.2 million kilometers (743,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 59 degrees. Image scale is 7 kilometers (4 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA09887: Pulling Away sur le site de la NASA.
Brilliant Prometheus pulls at the nearby inner strand of Saturn's F ring. Gravitational tugs from Prometheus are constantly reshaping this narrow ring.
Prometheus (86 kilometers, or 53 miles across at its widest point) is lit at right by the Sun and at left by reflected light from Saturn.
This view looks toward the sunlit side of the rings from about 40 degrees below the ringplane. The glow on the right side of the moon is due to light scattered within the camera optics. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on July 22, 2008. The view was acquired at a distance of approximately 546,000 kilometers (339,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 45 degrees. Image scale is 3 kilometers (2 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10456: Feeling Gravity's Pull sur le site de la NASA.
This view, like PIA08303, shows Prometheus with a streamer it has created in the inner edge of the F ring. Prometheus comes close to the inner edge of the ring once per orbit, perturbing the ring particles there. In 2009, the moon's orbit is expected to carry it repeatedly into the F ring core, an event that ring scientists are eagerly awaiting.
Prometheus is 102 kilometers (63 miles) across. This view looks toward the unlit side of the rings from about 40 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 16, 2006 at a distance of approximately 1.8 million kilometers (1.1 million miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 150 degrees. Scale in the original image was 11 kilometers (7 miles) per pixel. The image has been magnified by a factor of two.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
The flattened, potato-like form of Prometheus glides silently within the Roche Division, between Saturn's A and F rings.
Prometheus (86 kilometers, or 53 miles across at its widest point) is on the side of the rings closest to the Cassini spacecraft in this view. The image looks toward the sunlit side of the rings from about a degree below the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on May 2, 2008. The view was acquired at a distance of approximately 1.1 million kilometers (660,000 miles) from Prometheus. Image scale is 6 kilometers (4 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA09916: Spotting Prometheus sur le site de la NASA.
The Cassini spacecraft tracks the shepherd moon Prometheus as it orbits Saturn.
This image is part of a sequence designed to monitor the evolution of a streamer of material in the F ring for nearly a full orbit, as it follows Prometheus. Here, Prometheus is just about to pass behind the planet. The faint streamer lies below and to the right of Prometheus (86 kilometers, or 53 miles across), in the faint, inner strand of the F ring.
See PIA08397 for a movie sequence of Cassini images that shows Prometheus creating a streamer.
This view looks toward the unilluminated side of the rings from about 21 degrees above the ringplane. Saturn's upper atmosphere distorts the image of the rings near the planet's limb.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Aug. 9, 2008. The view was acquired at a distance of approximately 1.3 million kilometers (804,000 miles) from Prometheus. Image scale is 8 kilometers (5 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10463: Tracking the Shepherd sur le site de la NASA.
Prometheus emerges from Saturn's shadow in this image taken of the dark side of the rings.
Since it is nearing the equinox at Saturn, the Sun is very nearly in the ring plane, causing Prometheus to cast its own diminutive shadow on the F ring next to Saturn's enormous one.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 29, 2008 at a distance of approximately 1.24 million kilometers (771,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 27 degrees. Image scale is 7 kilometers (5 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA10535: Prometheus Emerges sur le site de la NASA.
A small moon appears from behind giant Saturn, accompanied by a warped view of the rings.
Prometheus (102 kilometers, or 63 miles across) is seen here between the A and F rings. Close to the planet, the image of the rings is slightly distorted by Saturn's upper atmosphere.
This view is similar to PIA09807, which features Pandora.
This view looks toward the unilluminated side of the rings from about 9 degrees above the ringplane. The image was taken in visible red light with the Cassini spacecraft narrow-angle camera on Nov. 30, 2007. The view was acquired at a distance of approximately 1.6 million kilometers (1 million miles) from Prometheus. Image scale is 10 kilometers (6 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Voir l'image PIA09810: Warp Zone sur le site de la NASA.
As it completed its first orbit of Saturn, Cassini zoomed in on the rings to catch this wondrous view of the shepherd moon Prometheus (102 kilometers, or 63 miles across) working its influence on the multi-stranded and kinked F ring.
The F ring resolves into five separate strands in this closeup view. Potato-shaped Prometheus is seen here, connected to the ringlets by a faint strand of material. Imaging scientists are not sure exactly how Prometheus is interacting with the F ring here, but they have speculated that the moon might be gravitationally pulling material away from the ring. The ringlets are disturbed in several other places. In some, discontinuities or "kinks" in the ringlets are seen; in others, gaps in the diffuse inner strands are seen. All these features appear to be due to the influence of Prometheus.
The image was taken in visible light with the narrow angle camera on Oct. 29, 2004, at a distance of about 782,000 kilometers (486,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 147 degrees. The image scale is 4.7 kilometers (2.9 miles) per pixel. The image has been magnified by a factor of two, and contrast was enhanced, to aid visibility.
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.
For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.
The oblong form of Prometheus glides by, trailing behind it wiggles in Saturn's ribbon-like F ring.
Prometheus (102 kilometers, or 63 miles across) causes a great deal of perturbation to the F ring, including kinks, knots and gores in the shape of the ring structure. By studying the moon and its interactions with the F ring scientists are learning a great deal about how ring structures form and evolve.
This view looks toward the unlit side of the rings from about 27 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 24, 2007 at a distance of approximately 1.5 million kilometers (900,000 miles) from Prometheus. Image scale is 9 kilometers (6 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Click on the image for movie of
Soft Collision
The moon Prometheus slowly collides with the diffuse inner edge of Saturn's F ring in this movie sequence of Cassini images. The oblong moon pulls a streamer of material from the ring and leaves behind a dark channel.
Once during its 14.7-hour orbit of Saturn, Prometheus (102 kilometers, or 63 miles across) reaches the point in its elliptical path, called apoapse, where it is farthest away from Saturn and closest to the F ring. At this point, Prometheus' gravity is just strong enough to draw a "streamer" of material out of the core region of the F ring.
Initially the dust-sized material drawn away from the ring appears to form a streamer pointing ahead of Prometheus in its orbit. (All orbital motion is towards the right in the movie.) Over time, the streamer falls increasingly farther behind Prometheus because material in the F ring is orbiting slower than the moon. The streamer gets longer and a darker "channel" starts to be seen (to the left of the streamer in the movie).
The creation of such streamers and channels occurs in a cycle that repeats each Prometheus orbit: when Prometheus again reaches apoapse, it draws another streamer of material from the F ring. But since Prometheus orbits faster than the material in the ring, this new streamer is pulled from a different location in the ring about 3.2 degrees (in longitude) ahead of the previous one.
In this way, a whole series of streamer-channels is created along the F ring. In some observations, 10 to 15 streamer-channels can easily be seen in the F ring at one time (see PIA07712). Eventually, a streamer-channel disappears as shearing forces (i.e., Keplerian shear) act to disperse the constituent dust particles.
The movie shows just under half of a complete streamer-channel cycle. The dark frames in the movie represent the period during which Prometheus and the F ring pass through Saturn's shadow.
The images in the movie were acquired by the Cassini spacecraft narrow-angle camera on Nov. 23 and 24, 2006. The movie sequence consists of 72 clear spectral filter images taken every 10.5 minutes over a period of about 12.5 hours.
The original images were cropped to show only the region around Prometheus and the nearby portion of the F ring. The movie covers the region between 138,000 and 142,000 kilometers (86,000 and 88,000 miles) radially from Saturn and 1 degree in longitude from Prometheus on each side. Each frame was reprojected such that the vertical axis represents distance from Saturn and the horizontal axis represents longitude around Saturn. Image scale is 10 kilometers (6 miles) per pixel in the vertical direction; the images cover 0.005 degrees of longitude in the horizontal direction. Because of the reprojection, the F ring appears straight, rather than slightly curved, as it otherwise would.
Since the F ring has an elliptical shape, its radial distance from Saturn varies by about 1,000 kilometers (620 miles) around the ring. This accounts for the apparent vertical movement of the ring over the course of the movie. Only a very small part of the ring appears in each of the reprojected frames, so the difference in the ring's radial distance from left to right across any single frame is small enough as to be effectively unnoticeable.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
Prometheus has just passed -- and gravitationally disturbed -- some of the fine particulate material in the F ring, creating the sheared gap visible in the inner strands of the ring. Prometheus is 102 kilometers (63 miles) across.
This view looks down from about 10 degrees above the ringplane. Prometheus and the rings are sunlit from below. At the lower right lies the outermost part of the A ring, which grows suddenly brighter outside of the 42-kilometer-wide (26-mile) Keeler Gap.
The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on Aug. 2, 2005, at a distance of approximately 632,000 kilometers (392,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 122 degrees. Image scale is 4 kilometers (2 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.
Prometheus pulls material from the tortured F ring in this highly detailed view. The aftereffects of the moon's other recent encounters with the ring are visible above as dark channels in the inner ringlet.
One of two F ring shepherd moons, Prometheus is 102 kilometers (63 miles) across.
This view looks toward the unilluminated side of the rings from about seven degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 1, 2007 at a distance of approximately 2.1 million kilometers (1.3 million miles) from Prometheus. Image scale is 12 kilometers (8 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.
In its own way, the shepherd moon Prometheus (102 kilometers, 63 miles across) is one of the lords of Saturn's rings. The little moon maintains the inner edge of Saturn's thin, knotted F ring, while its slightly smaller cohort Pandora (84 kilometers, or 52 miles across) guards the ring's outer edge.
This view is a composite of nine raw images combined in a way that improves resolution and reduces noise. The final image was magnified by a factor of five. One of the component images was previously released (see PIA06098).
The image clearly shows that Prometheus is not round, but instead has an oblong, potato-like shape. The moon was discovered during the Voyager mission, and scientists then noted ridges, valleys and craters on its surface. Hints of its varied topography are present in this view, although Cassini will likely obtain much better images of Prometheus later in the mission.
The component images were taken over about ten and a half minutes. During that time, the spacecraft's motion caused some blurring of the F ring in the background. Cassini was below the ring plane at the time the images were obtained, and the view here is across the rings toward the distant arm of the F ring. Sunlight is coming from below left.
These images were obtained with the Cassini spacecraft wide angle camera on July 1, 2004, around the time Cassini entered Saturn's orbit. The spacecraft's distance from the planet ranged from approximately 181,000 to 190,000 kilometers (112,000 to 118,000 miles) during the time the exposures were taken. The image scale is approximately 11 kilometers (7 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 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.
For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.
This sweeping view from Cassini gives a sense of the awesome scale of the planet's disk-like ring system, which stretches many thousands of kilometers into the distance. The shepherd moon Prometheus (102 kilometers, or 63 miles across) maintains a lonely sojourn with the thin, outer F ring.
A notable brightening of the F ring material is visible ahead of Prometheus in its orbit, near the right side of this image.
The view was obtained in visible light with the Cassini spacecraft narrow-angle camera on Feb. 18, 2005, at a distance of approximately 1 million kilometers (621,000 miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 105 degrees. The image scale is 6 kilometers (4 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.
Saturn's moon Prometheus is seen shepherding the inner edge of Saturn's F ring. Prometheus is 102 kilometers (63 miles) across and was captured in a close-up view by the Cassini spacecraft near the time of orbital insertion at Saturn (PIA06098). A number of clumps are visible here along the arcing F ring.
The image was taken with the Cassini spacecraft narrow angle camera on Aug. 5, 2004, at a distance of 8.2 million kilometers (5.1 million miles) from Saturn through a filter sensitive to visible green light. The image scale is 49 kilometers (33 miles) per pixel. Contrast was slightly enhanced to aid visibility.
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.
For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.