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Rhea-N00055690.jpgRhea and a "streak of light"58 visiteCerchiatura Bianca: un (nuovo) "streak" di luce bianca e molto intensa il quale, laddove non fosse il solito photoartifact, potrebbe concretare una interessante Anomalìa.
In realtà, la "striscia" in questione non ci pare proprio un photoartifact ed inoltre essa non dovrebbe neppure essere la semplice evidenza di un corpo celeste (un'altra luna di Saturno, ad esempio) il quale è rimasto non solo sovraesposto, ma anche strisciato (o "mosso") a causa della (eccessiva) durata della ripresa fotografica in rapporto alla velocità della Sonda . Per altro, anche osservando altri frames della Serie "N" - ad esempio N00055772 - la nostra sensazione è che il moto di Cassini, dal punto di vista dell'Osservatore e rispetto a Rhea, è ORIZZONTALE (da Sx a Dx) mentre lo streak è invece VERTICALE!
Deduzione logica: lo streak rappresenta un oggetto reale, situato ad una distanza indefinita da Cassini, il quale si sta muovendo rapidamente mentre asseconda una traiettoria incongrua rispetto a quella di Cassini.
Un "UFO", insomma...
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Saturn-PIA08140.jpgRestless Atmosphere (1)58 visiteThis atmosphere close-up shows bright clouds in Saturn's Northern Hemisphere being sheared apart. The clouds at the bottom of the image are tilted and stretched because the wind at those lower latitudes is moving much faster to the East than the wind at the higher latitudes near the top of the image, hence the shear.
This appearance suggests that these bright eddies are passive tracers of the atmosphere's motion - they appear, probably as a result of upwelling due to convection from below, and then they are sheared apart.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 16, 2006, at a distance of approximately 3,3 MKM (about 2 MMs) from Saturn. The image scale is roughly 19 Km (about 12 miles) per pixel.
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The Sun-P-021-01450.jpgJapanese Sun58 visitenessun commento
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Rhea-N00055743.jpgMoments of Rhea (5)58 visitenessun commento
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Rhea-N00056068.jpgDark Rhea and the Rings58 visitenessun commento
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Jupiter_s SouthPole-PIA07784.jpgThe South Pole of Jupiter58 visiteThe South Polar Regions shown here are less clearly visible because Cassini viewed them at an angle and through thicker atmospheric haze.
The round maps are polar stereographic projections that show the North or South Pole in the center of the map and the Equator at the edge.
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SOL792-2N196680545EFFAQCYP1911R0M1.jpgTracks, salts and sulphates (4) - Sol 79258 visitenessun commento
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Solar Eclypse 2006-tse2006_ayiomamitis_f.jpgThe "Diamond Ring"58 visiteDa "NASA - Picture of the Day" del 30 Marzo 2006:"The track of totality for the first solar eclipse of 2006 began early yesterday on the East coast of Brazil and ended half a world away at sunset in Western Mongolia. In between, the shadow of the Moon crossed the Atlantic Ocean, Northern Africa, central Asia and so came for a moment to the small Greek island of Kastelorizo in the Eastern Aegean.
Astronomer Anthony Ayiomamitis reports that the islanders and many eclipse-watching visitors were indeed treated to an inspiring display of the beautiful Solar Corona as totality lasted about 3 minutes.
As the total phase of the eclipse ended, he was able to capture this striking "Diamond Ring" image. In it, the first rays of sunlight shining through edge-on lunar valleys create the fleeting appearance of glistening diamonds set in a bright ring around the Moon's silhouette".
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Craters-Unnamed_Crater_with_Pedestal-PIA08029.jpgUnnamed Pedestal Crater in Promethei Terra (Original NASA/MGS/MSSS b/w Frame)58 visiteCaption NASA originale:"This MGS-MOC image shows a Pedestal Crater in the Promethei Terra Region. The Ejecta from an impact crater is usually rocky. The rocks in the Ejecta help shield the Terrain beneath the Ejecta from being eroded away by Wind. Thus, over time, some Craters appear to be raised on Pedestals defined by their Ejecta Blankets, because Wind has stripped away tons and tons of surrounding material".
Location near: 65,4° South Lat. and 264,7° West Long.
Image width: ~3 Km (~1,9 mi)
Illumination from: upper left
Season: Southern Autumn
Nota: un altro (relativamente) famoso cratere con (o su) piedistallo si trova su Venere ed è conosciuto con il nome di Cratere Adivar.
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Solar Corona.jpgThe 2006 Total Solar Eclipse: the Solar Corona58 visiteDa "NASA - Picture of the Day", del 7 Aprile 2006:"During a total Solar Eclipse, the Sun's extensive outer atmosphere (or Corona) is an awesome and inspirational sight. The subtle shades and shimmering features of the corona that engage the eye span a brightness range of over 10.000 to 1, making them notoriously difficult to capture in a single picture. But this composite of 33 digital images ranging in exposure time from 1/8000 to 1/5th of second comes very close to revealing the crown of the Sun in all its glory. The telescopic views were recorded from Side, Turkey, during the March 29, 2006, Solar Eclipse, a geocentric celestial event that was widely seen under nearly ideal conditions.
The composite also captures a pinkish prominence extending just beyond the upper edge of the eclipsed Sun".
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Q-S-BosporusRupes-PIA08047_modest.jpgBosporos Rupes58 visiteThis image was taken in the mid-latitudes of Mars' Southern Hemisphere near the giant Argyre Impact Basin. It is located just to the West of a prominent scarp known as Bosporos Rupes. The left side of the image shows cratered plains. Some of the craters are heavily mantled and indistinct, whereas others exhibit sharp rims and dramatic topography. The largest crater in this half of the image is about 2,5 Km wide. Mounds and ridges, which may be remnants of an ice-rich deposit, are visible on its floor. Three sinuous valleys occupy the center of the image. Valleys such as these were first observed in data returned by the NASA Mariner 9 spacecraft, which reached Mars in 1971. The right side of the image shows part of an impact crater that is approx. 20 Km in diameter. The furrowed appearance of the crater's inner wall suggests that it has been extensively modified, perhaps by landslides and flowing water. Like other craters in the area, the floor of this crater has a rough and dissected texture that is often attributed to the loss of ice-rich material.
This image was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard NASA's Mars Reconnaissance Orbiter spacecraft on March 24, 2006. The image is centered at 40,64° South Latitude, 303,49° East Longitude. The image is oriented such that North is 7° to the left of up. The range to the target was 2.044 Km (about 1.270 miles). At this distance the image scale is 2,04 mt (6,69 feet) per pixel, so objects as small as 6,1 mt (20 feet) are resolved. In total this image is 40,90 Km (about 25,41 miles) or 20.081 pixels wide and 11,22 Km (such as 6,97 miles) or 5.523 pixels high. The image was taken at a Local Mars Time of 07:30 and the scene is illuminated from the upper right with a solar incidence angle of 81,4° (this meaning that the Sun was about 8,6° above the horizon).
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ZYZ-Q-PlutoLatestColors.jpgThe "true" colors of Pluto (another interpretation)58 visiteUno studio sui possibili colori autentici di Plutone, realizzato dal bravo e modesto Ricercatore Don Davis, di cui abbiamo già apprezzato svariati studi ed elaborazioni sui "Colori del Sistema Solare" (Marte e Venere, in maniera particolare, sono - secondo noi - i suoi lavori più belli e riusciti).
Caption originale:"Pluto seems to have intriguing surface details, with pronounced contrast between white and yellow brown Regions. These regional contrasts have been largely detected by measurements of light changes as Pluto was eclipsed by its large satellite Charon, in the late 1980's. The albedo of Pluto ranges from 0,49 to 0,66, while darker more neutral colored Charon averages about 0,37".
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