| Ultimi arrivi - Saturn: the "Ringed Beauty" and His Moons |
Saturn-PIA08410.jpgElectrical Storm on Saturn's Upper Troposphere (natural colors; credits: NASA)57 visiteCaption NASA:"A bright, powerful, lightning-producing storm churns and coasts along the lane of Saturn's Southern Hemisphere nicknamed "Storm Alley" by scientists.
NASA's Cassini spacecraft detected this particular tempest after nearly 2 years during which Saturn did not appear to produce any large electrical storms of this kind. The storm appears as a bright, irregular splotch on the Planet near lower right.
Lightning flashes within the persistent storm produce radio waves, called Saturn Electrostatic Discharges, which the Cassini radio and plasma wave science instrument first detected on Nov. 27, 2007. Cassini's imaging cameras then spotted the storm, taking the images used to create this color view about a week later on Dec. 6, 2007.
This electrical storm is similar in appearance and intensity to those previously monitored by Cassini. All of these powerful electrostatic producing storms appeared at about 35° South Latitude on Saturn.
This storm has now been continuously tracked by Cassini for several months, whereas previous storms observed by the Spacecraft lasted for less than 30 days.
The view looks toward the un-illuminated side of the Rings from about 5° above the Ring-Plane. Tethys (about 1071 Km, or approx. 665 miles across) is seen here in the foreground, and casts its shadow onto the high Northern Latitudes.
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were acquired with the Cassini spacecraft wide-angle camera at a distance of approx. 1,7 MKM (1 MMs) from Saturn.
Image scale is roughly 97 Km (about 60 miles) per pixel".MareKromiumApr 30, 2008
|
|
Saturn-PIA08411.jpgElectrical Storm on Saturn's Upper Troposphere (approx. true colors; credits: NASA)59 visiteCaption NASA:"It is no Great Red Spot, but these two side-by-side views show the longest-lived electrical storm yet observed on Saturn by NASA's Cassini Spacecraft.
The views were acquired more than 3 months after the storm was first detected from its lightning-produced radio discharges on Nov. 27, 2007.
Cassini imaging scientists believe the storm to be a vertically extended disturbance that penetrates from Saturn's Lower to Upper Troposphere.
The view at left was created by combining images taken using red, green and blue spectral filters, and shows Saturn in colors that approximate what the human eye would see. The storm stands out with greater clarity in the sharpened, enhanced color view at right. This view combines images taken in infrared, green and violet light at 939, 567 and 420 nanometers respectively and represents an expansion of the wavelength region of the electromagnetic spectrum visible to human eyes. This view looks toward the un-illuminated side of the Rings from about 3° above the Ring-Plane.
Janus (about 181 Km, or approx. 113 miles across) appears as a dark speck just beneath the Rings in both images.
These images were obtained with the Cassini spacecraft wide-angle camera on March 4, 2008, at a distance of approx. 1,3 MKM (about 800.000 miles) from Saturn.
Image scale is roughly 74 Km (about 46 miles) per pixel".MareKromiumApr 30, 2008
|
|
Dione-PIA09886.jpgThe North Polar Regions of Dione (True Colors; credits: Lunexit)58 visiteCaption NASA:"The Cassini Spacecraft looks down, almost directly at the North Pole of Dione. The feature just left of the Terminator at the bottom is Janiculum Dorsa, a long, roughly North-South trending ridge. Lit terrain seen here is on the anti-Saturn and Trailing Sides of Dione.
The image was taken with the Cassini spacecraft narrow-angle camera on March 22, 2008 using a spectral filter sensitive to wavelengths of UV light centered at 338 nanometers. The view was acquired at a distance of approx. 650.000 Km (about 404.000 miles) from Dione and at a Sun-Dione-Spacecraft angle of 99°.
Image scale is roughly 4 Km (about 2 miles) per pixel".MareKromiumApr 23, 2008
|
|
UnknownObject-N00107570.jpgUnknown Object in the Space of Saturn58 visiteUna sorta di "Space Flare" si accende per pochi istanti nello Spazio di Saturno ed il "Caso" ha voluto che Cassini fosse lì, con gli "occhi aperti", pronto a fotografare.
Il risultato è questo: un curioso "flash" nel buio, dalla forma indefinibile e sulla cui Natura non ci è possibile investigare.
Forse non era nulla di importante, o forse si: ma comunque fosse, noi non lo sapremo mai.
Notate, infine, la curiosa (e sostanziale!) specularità dei corpi puntiformi ripresi.MareKromiumApr 23, 2008
|
|
Atlas-PIA09885.jpgAtlas and the "Roche Division"57 visiteCaption NASA:"Atlas, seen here, is one of the two moons that ply the Roche Division -- the region between Saturn's A and F-Rings. Prometheus also orbits within this Division.
This view looks toward flying-saucer-shaped Atlas (32 Km, or about 20 miles across at its widest point) and the unilluminated side of the Rings from about 37° above the Ring-Plane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 9, 2008. The view was obtained at a distance of approx. 1,5 MKM (such as about 925.000 miles) from Atlas and at a Sun-Atlas-Spacecraft angle of 44°.
Image scale is roughly 9 Km (approx. 6 miles) per pixel".MareKromiumApr 23, 2008
|
|
Tethys-PIA09878.jpgOdysseus in the Light55 visiteCaption NASA:"The Cassini spacecraft looks down onto high Northern Latitudes on Tethys, spying the enormous impact basin Odysseus.
Lit terrain seen here is on the anti-Saturn side of Tethys. North is towards the top of the image.
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. 765.000 Km (such as about 475.000 miles) from Tethys and at a Sun-Tethys-Spacecraft angle of 97°.
Image scale is roughly 5 Km (about 3 miles) per pixel".MareKromiumApr 12, 2008
|
|
Sun-N00107151.jpgSunshine through the Rings... (natural colors; credits: Lunexit)57 visiteCaption NASA:"Caption NASA:"N00107151.jpg was taken on April 10, 2008 and received on Earth on April 11, 2008. The camera was pointing toward SATURN, F-RING that, at the time, was approx. 613.189 Km away, and the image was taken using the CL1 and CL2 filters. This image has not been validated or calibrated".MareKromiumApr 11, 2008
|
|
Sun-N00107152.jpgSunshine through the Rings... (natural colors; credits: Lunexit)60 visiteCaption NASA:"Caption NASA:"N00107152.jpg was taken on April 10, 2008 and received on Earth on April 11, 2008. The camera was pointing toward SATURN, F-RING that, at the time, was approx. 611.114 Km away, and the image was taken using the CL1 and CL2 filters. This image has not been validated or calibrated".MareKromiumApr 11, 2008
|
|
Sun-N00107153.jpgSunshine through the Rings... (natural colors; credits: Lunexit)58 visiteCaption NASA:"N00107153.jpg was taken on April 10, 2008 and received on Earth on April 11, 2008. The camera was pointing toward SATURN, F-RING that, at the time, was approx. 609.375 Km away, and the image was taken using the CL1 and CL2 filters. This image has not been validated or calibrated".MareKromiumApr 11, 2008
|
|
Saturn-PIA09876~0.jpgNorthern Latitudes (Natural Colors; credits: NASA)57 visiteCaption NASA:"Saturn dominates this colorful view, taken from a vantage point high above the Rings. From here the Cassini Spacecraft can see the Rings' far side, where the dark shadow of Saturn abruptly terminates their visibility.
Mimas (about 397 Km, or approx. 247 miles across) casts its shadow onto the Planet's Northern Latitudes (just below center).
This view looks toward the unilluminated side of the Rings from about 27° above the Ring-Plane.
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were acquired with the Cassini spacecraft wide-angle camera on Feb. 26, 2008 at a distance of approx. 1,6 MKM (such as about 1 MMs) from Saturn.
Image scale is roughly 93 Km (about 58 miles) per pixel".MareKromiumApr 09, 2008
|
|
Janus-PIA09871.jpgJanus and Saturn (natural colors; credits: Lunexit)58 visiteCaption NASA:"The Cassini Spacecraft provides a window on the awesome scale of the Saturn System, with the Giant Planet dominating one of its smaller satellites.
Orbiting here, just outside the Main Ring System, is Janus.
This view looks toward the unilluminated side of the Rings from about 16° above the Ring-Plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 13, 2008. The view was obtained at a distance of approx. 1,6 MKM (about 1 MMs) from Janus and approx. 1,8 MKM (about 1,1 MMs) from Saturn.
Image scale is roughly 10 Km (about 6 miles) per pixel on Janus".MareKromiumApr 03, 2008
|
|
Enceladus-Cassini_big.jpgIs there "Life" underneath Enceladus?!?58 visiteCaption NASA:"Could life exist beneath Enceladus?
A recent flyby of Saturn's icy moon has bolstered this fascinating idea. Two years ago, images from the Cassini Spacecraft led astronomers to the undeniable conclusion that Saturn's moon Enceladus was spewing fountains of gas and ice crystals through cracks in its surface (the "Tiger Stripes").
Last month (February 2008), Cassini dove through some of these plumes and determined that they contained Water Vapor laced with small amounts of Methane as well as simple and complex organic molecules. Surprisingly, the plumes of Enceladus appear similar in make-up to many comets.
What's more, the temperature and density of the plumes indicate they might have originated from a warmer source - possibly a liquid source - beneath the surface.
A liquid water sea containing organic molecules is a good place to look for life.
Pictured above is a vertically exaggerated close-up of some long, venting Tiger Stripes. The computer composite was generated from images and shadows taken during the recent Cassini flyby.
Nine more flybys of Enceladus by Cassini are planned".MareKromiumMar 31, 2008
|
|
| 2245 immagini su 188 pagina(e) |
 |
|
|
|
|
62 | |
|
|
|
|
