Saturn: the "Ringed Beauty" and His Moons
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Mimas-PIA09880.jpgMimas is on Sight!55 visiteCaption NASA:"The Cassini spacecraft looks toward the high north on heavily cratered Mimas. The unmistakable Herschel impact crater is seen at lower left.
Lit terrain seen here is on the anti-Saturn side of Mimas (397 Km, or about 247 miles across).
Nota Lunexit: osservate bene la linea che disegna il profilo visibile di Mimas (se over-saturate il frame il lavoro sarà perfetto) e quindi notate la forma vagamente ovoidale di questa piccola luna.
Ed è proprio nella forma non sferica, comunque, che si cela la differenza tra "corpo celeste planetario" (piccolo o grande non importa) e "planetoide".
The moon's North Pole is up and tilted slightly toward Cassini. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 11, 2008. The view was acquired at a distance of approx. 795.000 Km (about 494.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, angle of 88°.
Image scale is roughly 5 Km (about 3 miles) per pixel".MareKromium
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Mimas-PIA10433.jpgMimas (possible True Colors; credits: Lunexit)113 visiteCaption NASA:"Deep craters riddle the pulverized, icy surface of Saturn's moon Mimas.
This view looks toward Southern Latitudes on Mimas from a vantage point 47° below the moon's Equator. North is towards the top of the image and rotated 40° to the right.
The image was taken in visible green light with the Cassini Spacecraft narrow-angle camera on June 16, 2008. The view was obtained at a distance of about 217.000 Km (approx. 135.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 83°.
Image scale is roughly 1 Km (about 0,6 mile) per pixel".MareKromium
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Mimas-PIA10467.jpgHol(e)y Mimas! (natural colors; credits: Lunexit)59 visiteCaption NASA:"The sun's low angle near the Terminator throws the craters of Mimas into stark relief.
This view looks toward high Northern Latitudes on Mimas (approx. 396 Km, or about 246 miles across) from a position 72° North of the moon's Equator. The North Pole is in darkness at center.
The image was taken in visible green light with the Cassini Spacecraft narrow-angle camera on Aug. 4, 2008. The view was obtained at a distance of approx. 153.000 Km (such as about 95.000 miles) from Mimas and at a Phase Angle of 106°.
Image scale is 918 meters (3011 feet) per pixel".MareKromium
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Mimas-PIA10469.jpgShadowed Mimas (natural colors; credits: Lunexit)56 visiteCaption NASA:"The shadow of Saturn's Rings sits upon the Northern Hemisphere of Mimas like a dark cap. In this Cassini Spacecraft view, which looks toward high Northern Latitudes on Mimas, the moon is just grazing the shadow of the Rings. The two distinct shadow regions seen here are the penumbra and the much darker umbra. An observer within the penumbral region on Mimas would have their view of the Sun partly blocked by the Rings.
For a viewer within the umbral region, the Rings would completely cover the Sun. However, since the Rings are not opaque, the Sun would still be dimly visible.
The image was brightened to reveal faint details within the eclipsed region, illuminated dimly by sunlight filtering through the Rings. Another view, PIA10467, was acquired a few minutes prior to this image, and shows a nearly identical Mimas (about 396 Km, or approx. 246 miles across) before the Rings' shadow obscured the surface.
The image was taken in visible light with the Cassini Spacecraft narrow-angle camera on Aug. 4, 2008. The view was acquired at a distance of approx. 143.000 Km (89.000 miles) from Mimas and from about 67° above the moon's Equator. The Phase Angle in the image is 106°.
Image scale is 856 meters (2808 feet) per pixel".MareKromium
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Mimas-PIA10517.jpgCrescent Mimas (possible natural colors; credits: Lunexit)62 visiteCaption NASA:"Mimas's lit crescent has the appearance of a golf ball thanks to its heavily cratered surface.
This image was taken with the Cassini Spacecraft narrow-angle camera on Oct. 24, 2008 using a spectral filter sensitive to wavelengths of IR light centered at 752 nanometers.
The view was obtained at a distance of approx. 189.000 Km (such as about 117.000 miles) from Mimas and at a Phase Angle of 136°.
Image scale is about 1 Km (such as 3707 feet) per pixel".MareKromium
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Mimas-PIA10548.jpgMimas over the Rings (possible True Colors credits: Lunar Explorer Italia68 visiteCaption NASA:"Gray Mimas appears to hover above the colorful Rings. The large crater seen on the right side of the moon is named for William Herschel, who discovered Mimas in 1789.
The image was taken using red, green and blue spectral filters; it was acquired with the Cassini Spacecraft narrow-angle camera on Sept. 9, 2007 at a distance of approx. 3,1 MKM (such as about 1,9 MMs) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 34°. Image scale is roughly 19 Km (about 12 miles) per pixel".MareKromium
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Mimas-PIA10589.jpgSunshine v/s Saturnshine on Mimas (Natural Colors; credits: Lunar Explorer Italia)54 visiteCaption NASA:"The transition from light to dark takes place on two fronts in this image of Mimas. The two Terminators that stretch across the moon are created by Sunshine across the North and Saturn-shine in the East.
This view looks toward the Trailing Hemisphere of Mimas. North on Mimas is up and rotated 33° to the right.
The image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on Jan. 23, 2009. The view was acquired at a distance of approx. 508.000 Km (about 316.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 152°.
Image scale is roughly 3 Km (a little less than 2 miles) per pixel".MareKromium
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Mimas-PIA11540.jpgHighlighting Herschel Crater54 visiteCaption NASA:"The Herschel crater dominates this view of Saturn's moon Mimas. The about 130-Km, or approx. 80-mile, wide crater is located in the Middle Latitudes of Mimas.
The most brightly lit Terrain seen here - lit by the Sun - is on the Leading Hemisphere of the moon. Light reflected from Saturn dimly lights the other side of the moon.
This view is centered on terrain at 37° North Lat. and 300° West Long. The North Pole of Mimas lies on the Terminator, about a quarter of the way inward from the top of the image.
Scale in the original image was 10 Km (about 6 miles) per pixel. The image has been magnified by a factor of two and contrast-enhanced to aid visibility. The image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on June 3, 2009.
The view was obtained at a distance of approx. 1,7 MKM (about 1,1 MMs) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 119°".MareKromium
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Mimas-PIA11642.jpg"Oblate" Mimas (Possible Natural Colors; credits: Lunexit)55 visiteCaption NASA:"The Cassini Spacecraft reveals the cratered surface of Mimas, a moon whose shape is flattened at the Poles. (see PIA07534 to learn more about why the moon has this oblate shape)
This view looks toward the Trailing Hemisphere of Mimas (approx. 396 Km, or about 246 miles, across). North on Mimas is up and rotated 1° to the left.
The image was taken in Visible Green Light with the Cassini Spacecraft narrow-angle camera on Oct. 14, 2009. The view was acquired at a distance of approx. 273.000 Km (such as about 170.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 5°.
Image scale is roughly 2 Km (about 1,4 miles) per pixel".MareKromium
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Mimas-PIA11661.jpgEclipsing Mimas54 visiteCaption NASA:"As the moon Enceladus eclipses its neighbor Mimas, Cassini records a scene possible only around the time of Saturn's approaching Equinox.
Seven images, each taken about 30" apart, were combined to create a movie which shows the shadow of Enceladus (about 504 Km, or approx. 313 miles, across) darkening Mimas (about 396 Km, or approx. 246 miles, across).
Although Saturn has eclipsed moons in previous images (see PIA11143 and PIA11508), this is the first time that Cassini has imaged one of Saturn's moons being eclipsed by another moon rather than the Planet.
The novel illumination geometry created as the Saturnian System approaches Equinox means that during this time moons orbiting in or near the plane of Saturn's Equatorial Rings can cast shadows onto the Rings and onto each other.
This image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on May 13, 2009. The view was obtained at a distance of approx. 1,3 MKM (about 808.000 miles) from Mimas and at a Phase Angle of 43°.
Image scale is roughly 8 Km (about 5 miles) per pixel".MareKromium
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Mimas-PIA12532.jpgLost in the Dark (Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)54 visiteCaption NASA:"Lit terrain seen here is on the Trailing Hemisphere of Mimas. This view looks toward the Northern, sunlit side of the Rings, from just above the Ring-Plane.
The image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on Nov. 3, 2009. The view was obtained at a distance of approx. 760.000 Km (about 472.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 61°.
Image scale is roughly 5 Km (a little more than 3 miles) per pixel. MareKromium
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Mimas-PIA12568.jpgThe "Eye" of Mimas54 visiteCaption NASA:"This mosaic, created from images taken by NASA's Cassini Spacecraft during its closest flyby of Saturn's moon Mimas, looks straight at the moon's huge Herschel Crater and reveals new insights about the moon's Surface. Bright-walled Craters, with Floors and surroundings - about 20% darker than the steep Crater Walls - are notable in this view. Mimas' original Surface, like the surfaces of most of the other major Saturnian moons without Atmospheres, is not pure ice but contains some dark impurities.
Herschel Crater (about 130 Km - approx. 80 miles - wide) and some of the smaller craters seen in this mosaic show relatively dark markings along the lower portion of their walls. Cassini scientists interpret this darkening as evidence for the gradual concentration of impurities from evaporating icy materials in areas where the dark impurities slide slowly down the Crater Wall. There, bright ice is baked away by the Sun and the vacuum of space.
At Herschel, the edge where the Darker Regions contact the Crater Floor, is interrupted by an extensive hummocky area. Scientists believe the hummocky texture came from the flow of melted ice that occurred during the impact that created the Crater itself. That melt filled the bottom of the Crater around the Central Peak.
Dark Streaks are seen making their way down the sides of some craters (marked red in the annotated version), often originating from pockets of dark contaminants embedded just below the rim of the crater wall. The pockets themselves likely represent small, pre-existing, dark-floored craters that were buried by the blanket of material that was thrown out from the newer impact that created the crater rim. The material from a newly exposed dark layer eventually moves downslope and forms a streak. Streaks are sometimes seen starting from the floors of smaller, dark-floored craters perched along Rims of larger Craters.
The interior of Herschel Crater is significantly less cratered than the continuous blanket of ejected material that extends radially outward from its rim. The violent meteor impact that excavated Herschel blasted pulverized debris, including massive chunks of ice, upward. The fallback of this ejected material over the Crater Rim created a thick Debris Blanket and dotted it with Secondary Craters. The presence of a fluid pool of melted material on the Crater Floor, which solidified after the debris fell, probably explains the relative absence of Craters on Herschel's Floor. These are common processes that should occur on bodies without Atmospheres throughout the Solar System. They may be accentuated on Mimas because of the large size of Herschel in comparison to Mimas' size.
Cassini came within about 9500 Km (approx. 5900 miles) of Mimas during its flyby on Feb. 13, 2010. This mosaic was created from 7 images taken that day in Visible Light with Cassini's narrow-angle camera. An eighth image, taken with the wide-angle camera on the same flyby, is used to fill in the lower right of the mosaic. The images were re-projected into an orthographic map projection. This view looks toward the Leading Hemisphere of Mimas.
This view is centered on terrain at about 10° South Latitude and 125° West Longitude. North is up.
The view was obtained at a distance of approx. 30.000 Km (about 19.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 27°.
Image scale is roughly 180 meters (600 feet) per pixel".MareKromium
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