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The Rings-PIA08285.jpgNot the Sun, but Aldebaran!55 visitenessun commento
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The Rings-PIA08287.jpgNot the Sun, but Aldebaran!55 visiteCaption NASA originale:"Cassini took a series of images on Sept. 9, 2006 as it watched the bright red giant star Aldebaran slip behind Saturn's Rings.
This type of observation is known as a "stellar occultation" and uses a star whose brightness is well known. As Cassini watches the rings pass in front, the star's light fluctuates, providing information about the concentrations of ring particles within the various radial features in the Rings.
Here, Cassini watches the star through the part of the Rings masked by Saturn's shadow. The view looks toward the sunlit side of the Rings from about 20° below the Ring-Plane. Bright Aldebaran is over exposed, creating thin vertical lines ("effetto goccia") on its image.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 9, 2006 at a distance of approx. 351.000 Km (such as about 218.000 miles) from Saturn. Image scale on the sky at the distance of Saturn is 2 Km (a little more than 1 mile) per pixel".
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Tethys-PIA08284-1.jpgTethys' transition (false colors)55 visiteCaption NASA originale:"An extreme false-color view of Tethys reveals a surface detail not visible in a monochrome view taken at the same time. The false-color view shows a color transition from the moon's Saturn-facing side (left) to a region its trailing side (bottom).
Near the top of the images, the central-peaked crater Telemachus lies in the deeply grooved terrain that marks the northern reaches of Ithaca Chasma.
To create the false-color view, ultraviolet, green and infrared images were combined into a single picture that isolates and maps regional color differences. This "color map" was then superposed over a clear-filter image that preserves the relative brightness across the body.
The combination of color map and brightness image shows how colors vary across Tethys' surface. The origin of the color differences is not yet understood, but may be caused by subtle differences in the surface composition or the sizes of grains making up the icy surface material".
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The Rings-PIA08290.jpgThe F-Ring (detail mgnf)55 visiteCaption NASA:"For some time, scientists have suspected the presence of tiny moonlets that orbit Saturn in association with the clumpy and braided-looking Ring. As the small satellites move close to the F-Ring core they leave a gravitational signature. In some cases they can draw out material in the form of a "streamer" - a miniature version of the interaction Cassini has witnessed between Prometheus and the F-Ring material. The dynamics of this interaction are the same, but the scale is different.
Scientists speculate that there could be several small moons with a variety of sizes involved in the creation of structures like the one seen here.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 25, 2006 at a distance of approx. 255.000 Km (about 159.000 miles) from Saturn and at phase angle of 29°. Scale in the original image was 1 Km (about 3.873 feet) per pixel. The image has been magnified by a factor of two and contrast enhanced".
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NGC-6357.jpgNGC 6357 - Emission Nebula and Open Star Cluster55 visite"...I closed my eyes,
Drew back the curtains,
To see for certain,
What I thought I knew,
Far far away, someone was weeping,
But the World was sleeping,
Any Dream will do..."
Dal Musical "Joseph and the Amazing Technicolor Dreamcoat"
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The Rings-PIA08295.jpgWhat's inside the Rings?55 visiteThe 2 prominent dark gaps in Saturn's A-Ring contain small embedded moons and a host of other intriguing features. Here, 3 unique ringlets are visible in the Encke Gap (about 325 Km wide). The innermost ringlet (topmost here) is faint but continuous. The center ringlet brightens substantially toward upper left and displays a few slight kinks. This ringlet is coincident with the orbit of Pan (about 26 Km across). The outermost ringlet is discontinuous, with two bright regions visible.
The narrower Keeler Gap (about 42 Km wide) hosts the moon Daphnis (7 Km across - not visible in this image), which raises waves in the Gap edges as it orbits Saturn. At lower left, faint ringlets flanking the bright F-Ring core are visible. These features were found by the Cassini spacecraft to be arranged into a spiral arm structure that winds around the Planet like a spring. The spiral may be caused by tiny moonlets or clumps of material that have smashed through the F-Ring core and liberated material.
This view looks toward the unlit side of the rings from about 23 degrees above the ringplane.
The image was taken in visible red light with the Cassini spacecraft narrow-angle camera on Sept. 11, 2006 at a distance of approximately 1.1 million kilometers (700,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 151 degrees. Image scale is about 6 kilometers (4 miles) per pixel.
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Saturn-PIA08297.jpgOut of the Dark...55 visiteCaption NASA:"As Ring particles emerge from the darkness of Saturn's shadow, they pass through a region of twilight. The Sun's light, refracted by the Planet's atmosphere, peeks around the limb, followed shortly by the Sun itself.
The "penumbra" is the narrow fringe Region of the Planet's shadow where part (but not all) of the Sun is visible around the side of the Planet, creating only a partial shadow there and making the shadow edge look fuzzy.
The A and F-Rings are captured here. This view looks toward the unlit side of the Rings from about 20° above the Ring-Plane. Two faint ringlets can be seen within the Encke Gap, which stretches out of the blackness at center and toward right.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 12, 2006 at a distance of approx. 1,5 MKM (about 900.000 miles) from Saturn and at a phase angle of 163°. Image scale is roughly 9 Km (about 5 miles)".
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Moon-Clem.JPG015 - The Moon (visible and near-infrared)55 visiteOne of the major scientific goals of the Clementine mission is to map the Moon in 11 different wavelengths in the visible and near-infrared parts of the spectrum. The filter colors of the Clementine cameras were carefully chosen to differentiate types of lunar surface material. In our first look at the global color, each Clementine image made by the UV/VIS camera has been reduced to its average value, producing a picture of the Moon at low resolution (about 50 kilometers per pixel). These pictures show the albedo (brightness) and color of the Moon from three aspects: the Earth-centered view (near side) with a 0 degree central longitude, and two far side views with 120 degrees East and 120 degrees West central longitudes. These images have been made by assigning colors to the relative reflectance values obtained through various filters, resulting in a map showing the compositional variation of the Moon.
Major compositional provinces in the highlands are evident. The large dark red-gray region on the far side is the South Pole-Aitken basin, an ancient impact feature that apparently contains rocks of distinct composition. A newly discovered compositional anomaly on the east limb of the Moon (pink area near center of 120 degrees East image) may be related to ancient flows of lava. The color picture shows that very high titanium lavas (deep blue and cyan colors) appear to be largely confined to the Oceanus Procellarum, Mare Imbrium, and Mare Tranquillitatis areas (near side). These views of the Moon in three colors only hint at the scientific richness contained within the Clementine global data, which will be investigated for years to come.
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as17-148-22607.JPGAS 17-148-22607 - Mother Earth55 visite
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as17-148-22669.JPGAS 17-148-22669 - Mother Earth55 visite
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as17-148-22686.JPGAS 17-148-22686 - Mother Earth55 visite
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as11-40-5931.JPGAS 11-40-5931 - "Buzz", Lunar Module & various Equipment55 visite110:55:49 MT. In this second photo from Neil's minus-Z (East) pan, Buzz has removed the Passive Seismometer Package from the SEQ bay. The foreground object with the handle is the Gold Camera, designed to take close-up photographs of the very top layer of the Lunar Soil. Note, also, the split rock at the right edge, just below the center of the photograph. This boulder was probably ejected from a nearby impact, possibly West Crater, and broke into two pieces when it hit. A different boulder, just to the left of center near the tip of the LM shadow in 5883, appears to have suffered a similar fate.
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