| |
| Ultimi commenti - Saturn: the "Ringed Beauty" and His Moons |
Saturnian_Lightnings-03.jpgSaturnian Lightnings151 visiteNASA's Cassini Spacecraft captured images of lightning at Saturn that allowed scientists to create the first movie showing lightning flashing on another Planet.
"The Visible Light images tell us a lot about the lightning," said Ulyana Dyudina, a Cassini imaging team associate based at the California Institute of Technology (Caltech) in Pasadena, Calif., who was the first to see the flashes. "Now we can begin to measure how powerful these storms are, where they form in the cloud layer and how the optical intensity relates to the total energy of the thunderstorms."
After waiting years for Saturn to dim enough for the Spacecraft's cameras to be able to detect bursts of light, scientists were able to create the movie, complete with an accompanying soundtrack that features the crackle of radio waves emitted when lightning bolts struck.
"This is the first time we have the visible lightning flash together with the radio data," said Georg Fischer, a radio and plasma wave science team associate based at the Space Research Institute in Graz, Austria. "Now that the radio and visible light data line up, we know for sure we are seeing powerful lightning storms."
Cassini, launched in 1997, and NASA's Voyager mission, launched in 1977, had previously captured radio emissions from storms on Saturn.
A belt around the gas giant, where Cassini previously detected radio emissions and bright, conservative clouds, even earned the nickname "storm alley." Cassini's cameras, however, had been unable to obtain pictures of lightning flashing.
Since the Robotic Spacecraft's arrival at Saturn in 2004, it has been difficult for Cassini to see lightning because the planet is very bright and reflective. Sunlight that shines off of Saturn's enormous Rings makes even the night side of Saturn brighter than a full-moon night on Earth.
The Equinox period around August 2009 finally brought enough darkness needed for Cassini's cameras. During Equinox, the Sun shone directly over the Planet's Equator, lighting the Rings edge-on only, leaving the bulk of the Rings in shadow.
The movie and radio data collected by the scientists suggest extremely powerful storms, with lightning that flashes as brightly as the brightest super-bolts of lightning on Earth, according to Andrew Ingersoll, a Cassini imaging science subsystem team member at Caltech.
"What's interesting is that the storms are as powerful or even more powerful at Saturn as on Earth," Ingersoll said. "But they occur much less frequently, with usually only one happening on the planet at any given time, though it can last for months."
The first images of lightning on Saturn were captured in August 2009, during a storm that lasted from January to October 2009, longer than any other observed lightning storm in the Solar System.
In order to make a video, scientists needed more pictures with brighter lightning and strong radio signals. Data collected during a shorter subsequent storm, which occurred from November through mid-December 2009, was also used.
The frames in the video were obtained over a period of 16 minutes on Nov. 30, 2009. The flashes lasted less than one second. The images also show a cloud as long as 1900 miles (3057,746 Km) across, with the regions illuminated by the lightning flashes reaching approx. 190 miles (305,7746 Km) in diameter. Scientists used the width of the lightning flashes to gauge the depth of the bolts below the cloud tops.
Lightning that strikes on Earth and Saturn emit radio waves at a frequency that can cause static on an AM radio. The audio in the video approximate that static sound, based on Saturn's electrostatic discharge signals that were detected by Cassini's radio and plasma wave science instrument.
Scientists monitoring the Cassini Orbiter were busy during this Equinox period, having already observed clumps in Saturn's Rings that are as high as the Rocky Mountains.
The Cassini-Huygens mission is a joint project involving NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of Caltech, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at the Jet Propulsion Laboratory.MareKromium03/01/20 at 12:18walthari: micidiali.....
|
|
Saturnian_Lightnings-03.jpgSaturnian Lightnings151 visiteNASA's Cassini Spacecraft captured images of lightning at Saturn that allowed scientists to create the first movie showing lightning flashing on another Planet.
"The Visible Light images tell us a lot about the lightning," said Ulyana Dyudina, a Cassini imaging team associate based at the California Institute of Technology (Caltech) in Pasadena, Calif., who was the first to see the flashes. "Now we can begin to measure how powerful these storms are, where they form in the cloud layer and how the optical intensity relates to the total energy of the thunderstorms."
After waiting years for Saturn to dim enough for the Spacecraft's cameras to be able to detect bursts of light, scientists were able to create the movie, complete with an accompanying soundtrack that features the crackle of radio waves emitted when lightning bolts struck.
"This is the first time we have the visible lightning flash together with the radio data," said Georg Fischer, a radio and plasma wave science team associate based at the Space Research Institute in Graz, Austria. "Now that the radio and visible light data line up, we know for sure we are seeing powerful lightning storms."
Cassini, launched in 1997, and NASA's Voyager mission, launched in 1977, had previously captured radio emissions from storms on Saturn.
A belt around the gas giant, where Cassini previously detected radio emissions and bright, conservative clouds, even earned the nickname "storm alley." Cassini's cameras, however, had been unable to obtain pictures of lightning flashing.
Since the Robotic Spacecraft's arrival at Saturn in 2004, it has been difficult for Cassini to see lightning because the planet is very bright and reflective. Sunlight that shines off of Saturn's enormous Rings makes even the night side of Saturn brighter than a full-moon night on Earth.
The Equinox period around August 2009 finally brought enough darkness needed for Cassini's cameras. During Equinox, the Sun shone directly over the Planet's Equator, lighting the Rings edge-on only, leaving the bulk of the Rings in shadow.
The movie and radio data collected by the scientists suggest extremely powerful storms, with lightning that flashes as brightly as the brightest super-bolts of lightning on Earth, according to Andrew Ingersoll, a Cassini imaging science subsystem team member at Caltech.
"What's interesting is that the storms are as powerful or even more powerful at Saturn as on Earth," Ingersoll said. "But they occur much less frequently, with usually only one happening on the planet at any given time, though it can last for months."
The first images of lightning on Saturn were captured in August 2009, during a storm that lasted from January to October 2009, longer than any other observed lightning storm in the Solar System.
In order to make a video, scientists needed more pictures with brighter lightning and strong radio signals. Data collected during a shorter subsequent storm, which occurred from November through mid-December 2009, was also used.
The frames in the video were obtained over a period of 16 minutes on Nov. 30, 2009. The flashes lasted less than one second. The images also show a cloud as long as 1900 miles (3057,746 Km) across, with the regions illuminated by the lightning flashes reaching approx. 190 miles (305,7746 Km) in diameter. Scientists used the width of the lightning flashes to gauge the depth of the bolts below the cloud tops.
Lightning that strikes on Earth and Saturn emit radio waves at a frequency that can cause static on an AM radio. The audio in the video approximate that static sound, based on Saturn's electrostatic discharge signals that were detected by Cassini's radio and plasma wave science instrument.
Scientists monitoring the Cassini Orbiter were busy during this Equinox period, having already observed clumps in Saturn's Rings that are as high as the Rocky Mountains.
The Cassini-Huygens mission is a joint project involving NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of Caltech, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at the Jet Propulsion Laboratory.MareKromium02/28/20 at 17:29MareKromium: Ma ve li immaginate i "fulmini" nell'...
|
|
Saturn-N00027024.jpgSomething is moving: is it a moon or a spaceship? (3)58 visitevedi i commenti ai frames che precedono02/11/20 at 12:39MareKromium: Quotone! D'accordo con entrambi!
|
|
Saturn-N00027024.jpgSomething is moving: is it a moon or a spaceship? (3)58 visitevedi i commenti ai frames che precedono02/11/20 at 12:28Anakin: per me ? assolutamente una luna venuta mossa per l...
|
|
Saturn-N00027024.jpgSomething is moving: is it a moon or a spaceship? (3)58 visitevedi i commenti ai frames che precedono02/11/20 at 08:35walthari: non sono un esperto di ottica ma potrebbe starci
|
|
Saturn-N00027024.jpgSomething is moving: is it a moon or a spaceship? (3)58 visitevedi i commenti ai frames che precedono02/09/20 at 15:50MareKromium: ...ed anche questa sequenza rappresenta un "o...
|
|
Saturn-N00027023.jpgSomething is moving: is it a moon or a spaceship? (2)54 visiteDa questo secondo frame riusciamo a cogliere, proprio sulla linea del terminatore del corpo luminoso, un rilievo che ci fa optare in maniera decisa verso l'ipotesi "luna di Saturno mossa" (Mimas, probabilmente). Si tratta, come avrete capito, di un esercizio: ogni immagine che vediamo e che esaminiamo può nascondere qualche enigma: scoprirlo ed interpretarlo è il lavoro di ogni Anomaly Hunter. Però è anche vero che tanti enigmi nascono a seguito di errori, malintesi e/o vere e proprie carenze di dati ed informazioni utili. Questa serie di tre frames - che è comunque curiosa ed interessante - è un esempio di come sia facile credere di vedere ET!...02/09/20 at 15:49MareKromium: ...ed anche questa sequenza rappresenta un "o...
|
|
Saturn-N00027022.jpgSomething is moving: is it a moon or a spaceship? (1)57 visiteAncora un enigma e, ancora una volta l'immagine è - secondo noi -davvero difficile da interpretare. Vi offriamo 3 frames ripresi dalla Sonda Cassini i quali ci mostrano la porzione più esterna degli Anelli di Saturno (per altro leggermente sovraesposti) e, in alto, proprio alla Vostra estrema Sn, un oggetto che emana una notevole luce e che, nell'arco dei tre frames, si sposta visibilmente dall'angolo alto a Sn sin quasi al centro del riquadro (ma sempre restando sul margine superiore dell'immagine). Abbiamo subito pensato che si trattasse di una delle lune di Saturno che, come è accaduto altre volte, è rimasta "mossa" (e così ci sembra, effettivamente). Ma è la rapidità di movimento dell'oggetto che ci ha lasciati perplessi. Certo è, però, che non sappiamo (grazie alla pochezza di dati utili rilasciati dalla NASA) l'intervallo di tempo intercorrente fra i vari scatti. Secondi, minuti oppure ore? Ma è proprio da questa informazione che dipende la risposta all'interrogativo che intitola le immagini!02/09/20 at 15:49MareKromium: ...ed anche questa sequenza rappresenta un "o...
|
|
Atlas,_Daphins_and_Pan-PIA21449.jpgAtlas, Daphnis and Pan156 visiteCaption NASA:"This montage of views from NASA's Cassini Spacecraft shows three of Saturn's Small Ring moons: Atlas, Daphnis and Pan at the same scale for ease of comparison.
Two differences between Atlas and Pan are obvious in this montage. Pan's Equatorial Band is much thinner and more sharply defined, and the central mass of Atlas (the part underneath the smooth Equatorial Band) appears to be smaller than that of Pan.
All of these images were taken using the Cassini Spacecraft Narrow-Angle Camera. The images of Atlas were acquired on April 12, 2017, at a distance of about 10.000 miles (approx. 16,0093 Km) and at a Sun-moons-Spacecraft angle (or Phase Angle) of 37°. All three images are oriented so that North is up".MareKromium01/23/20 at 18:38MareKromium: Si. E' una via di mezzo fra un panino imbottit...
|
|
Atlas,_Daphins_and_Pan-PIA21449.jpgAtlas, Daphnis and Pan156 visiteCaption NASA:"This montage of views from NASA's Cassini Spacecraft shows three of Saturn's Small Ring moons: Atlas, Daphnis and Pan at the same scale for ease of comparison.
Two differences between Atlas and Pan are obvious in this montage. Pan's Equatorial Band is much thinner and more sharply defined, and the central mass of Atlas (the part underneath the smooth Equatorial Band) appears to be smaller than that of Pan.
All of these images were taken using the Cassini Spacecraft Narrow-Angle Camera. The images of Atlas were acquired on April 12, 2017, at a distance of about 10.000 miles (approx. 16,0093 Km) and at a Sun-moons-Spacecraft angle (or Phase Angle) of 37°. All three images are oriented so that North is up".MareKromium01/23/20 at 15:18Anakin: Pan è davvero strano
|
|
Tethys-PIA09915-1.jpgShall Odysseus ever find Ithaca? (Stretched Absolute Natural Colors; credits for the add. process.: Dr Paolo C. Fienga-LXTT-IPF)136 visiteCaption NASA:"From a highly inclined orbit, the Cassini Spacecraft looks toward far Northern Latitudes on Tethys.
Here, the spacecraft was above a position about 45° North of the moon's Equator.
This vantage point afforded a view of the moon's three most recognizable features: the Ithaca Chasma Canyon System (at lower right), Odysseus Crater (at upper left) and the Equatorial Band of Darker Terrain (at lower left).
Lit terrain seen here is on the Leading Hemisphere of Tethys (1062 Km, or approx. 660 miles across). North is up.
The image was taken in Visible Light with the NASA - Cassini Spacecraft narrow-angle camera on April 29, 2008.
The view was obtained at a distance of approx. 991.000 Km (such as about 616.000 miles) from Tethys and at Phase Angle of 73°.
Image scale is roughly 6 Km (about 4 miles) per pixel".MareKromium01/09/20 at 13:05MareKromium: The flight of the "Wild Geese"..... (par...
|
|
Tethys-PIA09915-1.jpgShall Odysseus ever find Ithaca? (Stretched Absolute Natural Colors; credits for the add. process.: Dr Paolo C. Fienga-LXTT-IPF)136 visiteCaption NASA:"From a highly inclined orbit, the Cassini Spacecraft looks toward far Northern Latitudes on Tethys.
Here, the spacecraft was above a position about 45° North of the moon's Equator.
This vantage point afforded a view of the moon's three most recognizable features: the Ithaca Chasma Canyon System (at lower right), Odysseus Crater (at upper left) and the Equatorial Band of Darker Terrain (at lower left).
Lit terrain seen here is on the Leading Hemisphere of Tethys (1062 Km, or approx. 660 miles across). North is up.
The image was taken in Visible Light with the NASA - Cassini Spacecraft narrow-angle camera on April 29, 2008.
The view was obtained at a distance of approx. 991.000 Km (such as about 616.000 miles) from Tethys and at Phase Angle of 73°.
Image scale is roughly 6 Km (about 4 miles) per pixel".MareKromium01/09/20 at 06:50Anakin: The flight of a stone
|
|
| 920 immagini su 77 pagina(e) |
|
|
|
|
|
13 | |
|
|
|
|
|
|
