Narrow Search
 
 
Advanced Search

Browse All : Uranus of Washington, D.C.

Printer Friendly
1-26 of 26
     
     
Saturn's Blue Cranium
Description Saturn's Blue Cranium
Full Description Saturn's northern hemisphere is presently a serene blue, more befitting of Uranus or Neptune, as seen in this natural color image from Cassini. Light rays here travel a much longer path through the relatively cloud-free upper atmosphere. Along this path, shorter wavelength blue light rays are scattered effectively by gases in the atmosphere, and it is this scattered light that gives the region its blue appearance. Why the upper atmosphere in the northern hemisphere is so cloud-free is not known, but may be related to colder temperatures brought on by the ring shadows cast there. Shadows cast by the rings surround the pole, looking almost like dark atmospheric bands. The ring shadows at higher latitudes correspond to locations on the ringplane that are farther from the planet -- in other words, the northernmost ring shadow in this view is made by the outer edge of the A ring. Spots of bright clouds also are visible throughout the region. This view is similar to an infrared image obtained by Cassini at nearly the same time (see http://photojournal.jpl.nasa.gov/catalog/PIA06567). The infrared view shows a great deal more detail in the planet's atmosphere, however. Images obtained using red, green and blue spectral filters were combined to create this color view. The images were taken with the Cassini spacecraft wide angle camera on Dec. 14, 2004, at a distance of 719,200 kilometers (446,900 miles) from Saturn. The image scale is about 39 kilometers (24 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 images visit the Cassini imaging team home page http://ciclops.org . *Credit:* NASA/JPL/Space Science Institute
Date February 8, 2005
Old and New Again
Description Old and New Again
Full Description Miranda, an icy moon of Uranus (see PIA 00141). Miranda is 470-kilometers-wide (290 miles), nearly as large as Enceladus (504 kilometers, or 313 miles wide). The similarities in size and tectonic history on these objects may suggest that remarkably similar physical processes have controlled the separate geological evolutions of these bodies. The images that comprise this mosaic were obtained during Cassini's closest approach to Enceladus on March 9, 2005. The images was taken in visible green light with the Cassini spacecraft narrow-angle camera at a distance of approximately 29,000 kilometers (18,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 46 degrees. Resolution in the original images is about 170 meters (560 feet) 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 . *Credit:* NASA/JPL/Space Science Institute, This false-color Cassini mosaic of Saturn's moon Enceladus captures in a single view, much of the frigid moon's diverse geology. Cratered terrain dominates most of the scene. The relatively dense accumulation of impact craters implies that this terrain is among the oldest on the moon's surface. Near the bottom of the picture is a crater 20 kilometers wide (12-mile) with a prominent dome-shaped structure in its center. The entire area is transected by a complex web of fractures and faults, some are as narrow as a few hundred meters, others as wide as 5 kilometers (3 miles). The rims and interiors of many craters seem to be sliced by a pervasive system of narrow, parallel grooves into slabs or lanes that typically are a kilometer (about a half-mile) in width. The widely varied appearances of fractures in this region attest to the fact that the surface of Enceladus has been shaped by a long history of intense tectonic activity. The oldest fractures are characterized by a soft, muted appearance and are overprinted by numerous, superimposed impact craters. More recent fractures exhibit topographic relief that is relatively "crisp" in appearance, and they appear to slice through pre-existing impact craters and older fractures. On the right side of the image is a conspicuous and twisted network of ridges and troughs forming a distinct tectonic region on Enceladus. The paucity of craters and the sharp appearance of the topography in this area indicate that this is a relatively young terrain on Enceladus. This view is a composite of images taken using filters sensitive to ultraviolet (centered at 338 nanometers), green (centered at 568 nanometers), and near-infrared (centered at 930 nanometers) light, and has been processed to accentuate subtle color differences. The uppermost surface of these terrains has a relatively uniform grayish color in this picture, suggesting that it is covered with materials of homogeneous composition and grain size. However, many of the fractures reveal a distinctly different color (represented by pale-bluish tones in this false-color image) than the typical surface materials. These "colored" fractures seem to penetrate down to a material that is texturally or compositionally different than most of the material at the surface. One possibility is that the walls of the fractures expose outcrops of solid ice, or ice with different grain-sizes compared to powdery surface materials that blanket flat-lying surfaces. It is also possible that the color identifies some compositional difference between buried ice and ice at the surface. The distinct coloration of "youthful" fracture walls are nearly absent in the oldest fractures. This is consistent with the possibility that the older fractures are covered with a drape of particulate material which mantles nearly all the oldest features on the satellite. In the early 1980's, NASA's Voyager mission to the outer planets revealed a strikingly similar arrangement of terrains on
Date March 16, 2005
Charon Discovery Image
title Charon Discovery Image
date 06.22.1978
description On 22 June 1978, an astronomer at the U.S. Naval Observatory in Washington, D.C. was making routine measurements of photographic plates taken with the 1.55-meter (61-inch) Kaj Strand Astrometric Reflector at the USNO Flagstaff Station in Arizona. The purpose of these images was to refine the orbit of the far-flung planet Pluto to help compute a better ephemeris for this distant object. Astronomer James W. Christy had noticed that a number of the images of Pluto appeared elongated, but images of background stars on the same plate did not. Other plates showed the planet as a tiny, round dot. Christy examined a number of Pluto images from the USNO archives, and he noticed the elongations again. Furthermore, the elongations appeared to change position with respect to the stars over time. After eliminating the possibility that the elongations were produced by plate defects and background stars, the only plausible explanation was that they were caused by a previously unknown moon orbiting Pluto at a distance of about 19,600 kilometers (12,100 miles) with a period of just over six days. On 7 July 1978, the discovery was formally announced to the astronomical community and the world by the IAU Central Bureau for Astronomical Telegrams via IAU Circular 3241. The discovery received the provisional designation "1978 P 1", Christy proposed the name "Charon", after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto's underworld. Over the course of the next several years, another USNO astronomer, the late Robert S. Harrington, calculated that Pluto and its newly-found moon would undergo a series of mutual eclipses and occultations, beginning in early 1985. On 17 February 1985 the first successful observation of one of these transits was made at with the 0.9-meter (36-inch) reflector at the University of Texas McDonald Observatory, within 40 minutes of Harrington's predicted time. The IAU Circular announcing these confirming observations was issued on 22 February 1985. With this confirmation, the new moon was officially named Charon. Pluto was discovered at Lowell Observatory in 1930 by the late Clyde W. Tombaugh, an amateur astronomer from Kansas who was hired by the Observatory specifically to photograph the sky with a special camera and search for the planet predicted by the Observatory's founder, Percival Lowell. Lowell had deduced the existence of a "Planet X" by studying small anomalies in the orbits of Uranus and Neptune. As it turned out, Pluto's discovery was almost entirely serendipitous, Pluto's tiny mass was far too small to account for the anomalies, which were resolved when Voyager 2 determined more precise masses for Uranus and Neptune. The discovery of Charon has led to a much better understanding of just how tiny Pluto is. Its diameter is about 2274 km (1413 miles), and its mass is 0.25% of the mass of the Earth. Charon has a diameter of about 1172 kilometers (728, miles) and a mass of about 22% that of Pluto. The two worlds circle their common center of mass with a period of 6.387 days and are locked in a "super-synchronous" rotation: observers on Pluto's surface would always see Charon in the same part of the sky relative to their local horizon. Normally Pluto is considered the most distant world in the solar system, but during the period from January 1979 until February 1999 it was actually closer to the Sun than Neptune. It has the most eccentric and inclinced orbit of any of the major planets. This orbit won't bring Pluto back to its discovery position until the year 2178! *Image Credit*: U.S. Naval Observatory
Hubble Provides Infrared Vie …
Title Hubble Provides Infrared View of Moon, Ring, and Clouds
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
Hands-On Book of Hubble Imag …
Title Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe
The Colorful Demise of a Sun …
Title The Colorful Demise of a Sun-like Star
Dusty Planetary Disks Around …
Title Dusty Planetary Disks Around Two Nearby Stars Resemble Our Kuiper Belt
General Information What is a News Nugget? News Nuggets are bulletins from the world of astronomy. These two bright debris disks of ice and dust appear to be the equivalent of our own solar system's Kuiper Belt, a ring of icy rocks outside the orbit of Neptune and the source of short-period comets. The disks encircle the types of stars around which there could be habitable zones and planets for life to develop. The disks seem to have a central area cleared of debris, perhaps by planets.
Saturn's Blue Cranium
PIA06177
Sol (our sun)
Imaging Science Subsystem - …
Title Saturn's Blue Cranium
Original Caption Released with Image Saturn's northern hemisphere is presently a serene blue, more befitting of Uranus or Neptune, as seen in this natural color image from Cassini. Light rays here travel a much longer path through the relatively cloud-free upper atmosphere. Along this path, shorter wavelength blue light rays are scattered effectively by gases in the atmosphere, and it is this scattered light that gives the region its blue appearance. Why the upper atmosphere in the northern hemisphere is so cloud-free is not known, but may be related to colder temperatures brought on by the ring shadows cast there. Shadows cast by the rings surround the pole, looking almost like dark atmospheric bands. The ring shadows at higher latitudes correspond to locations on the ringplane that are farther from the planet--in other words, the northernmost ring shadow in this view is made by the outer edge of the A ring. Spots of bright clouds also are visible throughout the region. This view is similar to an infrared image obtained by Cassini at nearly the same time (see PIA06567 [ http://photojournal.jpl.nasa.gov/catalog/PIA06567 ]). The infrared view shows a great deal more detail in the planet's atmosphere, however. Images obtained using red, green and blue spectral filters were combined to create this color view. The images were taken with the Cassini spacecraft wide angle camera on Dec. 14, 2004, at a distance of 719,200 kilometers (446,900 miles) from Saturn. The image scale is about 39 kilometers (24 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 [ http://saturn.jpl.nasa.gov ] and the Cassini imaging team home page, http://ciclops.org [ http://ciclops.org ].
Old and New Again
PIA06207
Saturn
Imaging Science Subsystem - …
Title Old and New Again
Original Caption Released with Image Miranda, an icy moon of Uranus (see PIA00141 [ http://photojournal.jpl.nasa.gov/catalog/PIA00141 ]). Miranda is 470-kilometers-wide (290 miles), nearly as large as Enceladus (504 kilometers, or 313 miles wide). The similarities in size and tectonic history on these objects may suggest that remarkably similar physical processes have controlled the separate geological evolutions of these bodies. The images that comprise this mosaic were obtained during Cassini's closest approach to Enceladus on March 9, 2005. The images was taken in visible green light with the Cassini spacecraft narrow-angle camera at a distance of approximately 29,000 kilometers (18,000 miles) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 46 degrees. Resolution in the original images is about 170 meters (560 feet) 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 [ http://saturn.jpl.nasa.gov ] and the Cassini imaging team home page, http://ciclops.org [ http://ciclops.org ]., This false-color Cassini mosaic of Saturn's moon Enceladus captures in a single view, much of the frigid moon's diverse geology. Cratered terrain dominates most of the scene. The relatively dense accumulation of impact craters implies that this terrain is among the oldest on the moon's surface. Near the bottom of the picture is a crater 20 kilometers wide (12-mile) with a prominent dome-shaped structure in its center. The entire area is transected by a complex web of fractures and faults, some are as narrow as a few hundred meters, others as wide as 5 kilometers (3 miles). The rims and interiors of many craters seem to be sliced by a pervasive system of narrow, parallel grooves into slabs or lanes that typically are a kilometer (about a half-mile) in width. The widely varied appearances of fractures in this region attest to the fact that the surface of Enceladus has been shaped by a long history of intense tectonic activity. The oldest fractures are characterized by a soft, muted appearance and are overprinted by numerous, superimposed impact craters. More recent fractures exhibit topographic relief that is relatively "crisp" in appearance, and they appear to slice through pre-existing impact craters and older fractures. On the right side of the image is a conspicuous and twisted network of ridges and troughs forming a distinct tectonic region on Enceladus. The paucity of craters and the sharp appearance of the topography in this area indicate that this is a relatively young terrain on Enceladus. This view is a composite of images taken using filters sensitive to ultraviolet (centered at 338 nanometers), green (centered at 568 nanometers), and near-infrared (centered at 930 nanometers) light, and has been processed to accentuate subtle color differences. The uppermost surface of these terrains has a relatively uniform grayish color in this picture, suggesting that it is covered with materials of homogeneous composition and grain size. However, many of the fractures reveal a distinctly different color (represented by pale-bluish tones in this false-color image) than the typical surface materials. These "colored" fractures seem to penetrate down to a material that is texturally or compositionally different than most of the material at the surface. One possibility is that the walls of the fractures expose outcrops of solid ice, or ice with different grain-sizes compared to powdery surface materials that blanket flat-lying surfaces. It is also possible that the color identifies some compositional difference between buried ice and ice at the surface. The distinct coloration of "youthful" fracture walls are nearly absent in the oldest fractures. This is consistent with the possibility that the older fractures are covered with a drape of particulate material which mantles nearly all the oldest features on the satellite. In the early 1980's, NASA's Voyager mission to the outer planets revealed a strikingly similar arrangement of terrains on
Uranus moon - 1985U1
PIA01357
Unknown target/parent relati …
Imaging Science Subsystem - …
Title Uranus moon - 1985U1
Original Caption Released with Image Several craters are seen on the surface of 1985U1, one of several small moons of Uranus discovered by Voyager 2. The spacecraft acquired this single image -- the only close-up it obtained of any of the new moons -- on Jan. 24, 1986. At the time, Voyager was at a distance of about 500,000 kilometers (300,000 miles) from 1985U1, yielding a resolution of about 10 km (6 mi) in this clear-filter, narrow-angle image. The moon was found Dec. 3O, 1985, it was the first and largest of nearly a dozen satellites discovered by the spacecraft cameras. This image shows 1985U1 to be a dark, nearly spherical object, with a diameter of about 150 km (90 mi), the dark surface reflects only 7 percent of the incident light. The picture was inserted into the Voyager encounter sequence late in its development. This image has had a complex history, having been recorded on the spacecraft tape recorder and first played back during the late afternoon of Jan. 24. An antenna-pointing problem at one of the Australian tracking stations led to loss of the data, so the image had to be transmitted a second time. It was successfully received shortly before 6 p.m. PST Jan. 26. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Saturn and its rings
PIA01969
Sol (our sun)
Imaging Science Subsystem - …
Title Saturn and its rings
Original Caption Released with Image Voyager 1 looked back at Saturn on Nov. 16, 1980, four days after the spacecraft flew past the planet, to observe the appearance of Saturn and its rings from this unique perspective. A few of the spokelike ring features discovered by Voyager appear in the rings as bright patches in this image, taken at a distance of 5.3 million kilometers (3.3 million miles) from the planet. Saturn's shadow falls upon the rings, and the bright Saturn crescent is seen through all but the densest portion of the rings. From Saturn, Voyager 1 is on a trajectory taking the spacecraft out of the ecliptic plane, away from the Sun and eventually out of the solar system (by about 1990). Although its mission to Jupiter and Saturn is nearly over (the Saturn encounter ends Dec. 18, 1980), Voyager 1 will be tracked by the Deep Space Network as far as possible in an effort to determine where the influence of the Sun ends and interstellar space begins. Voyager 1's flight path through interstellar space is in the direction of the constellation Ophiuchus. Voyager 2 will reach Saturn on August 25, 1981, and is targeted to encounter Uranus in 1986 and possibly Neptune in 1989. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, California.
1-26 of 26