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ZZ-Mercury-Volcanic_Regions-Plains-PIA16428-PCF-LXTT-IPF.jpgVolcanic Region (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)70 visiteMany Regions of Mercury's Surface show a relatively smooth and dark brown/reddish-colored Terrain (with almost black patches near and around the Rims of the major Impact Craters) that, in a way, appears to have "flooded" (---> quickly covered, either in whole or in part) low-lying Areas and, at the same time, which has also partially filled (and/or, here and there, almost completely buried) what seem to be the oldest Impact Craters existing on the Surface. Said that, we can reasonably speculate that these smooth Plains could have formed, in a very distant past of the Innermost Planet of the Solar System, as a consequence of the occurrence of some powerful Volcanic Activity which, in fact, ended up by - litterally - "drowning" these Regions with - and in - extremely voluminous amounts of, most likely, low-viscosity Basaltic Lavas.
Notice that the beautiful colors of the Mercurian Surface, as well as all the details of the Terrain seen here, all appear to be extremely clear, sharp and well visible, (also) thanks to to fact that the Sun, at the time that the picture was taken, was relatively high in the Sky (59,2° on the Local Horizon, to be exact).
Date acquired: July, 21st, 2012
Images Mission Elapsed Time (MET): 251402330, 251402350, and 251402334
Images ID: 2244264, 2244269, and 2244265
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 8,27° South
Center Longitude: 113,1° East
Scale: this scene is approx. 475 Km across
This picture (which is an Original NASA - MESSENGER Spacecraft color frame published on the NASA - Planetary Photojournal with the ID n. PIA 16428) has been additionally processed and then re-colorized in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - MESSENGER Spacecraft and then looked down, towards the Surface of Mercury), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among other things, the existence of different Elements (Minerals) present on the Surface of Mercury, each having a different Albedo (---> Reflectivity) and Chemical Composition.MareKromium
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ZZ-Mercury-Volcanic_feature-Collapse_Pit-PIA13468-PCF-LXTT.jpgCollapse Pit-Chain inside Picasso Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)188 visiteThe Crater pictured in the center of this image was recently named Picasso, in honor of the Spanish painter and sculptor Pablo Picasso (1881-1973). This Crater, first imaged during MESSENGER's third Mercury Fly-By, has drawn scientific attention because of the large, arc-shaped Pit-Chain located on the Eastern side of its Floor. Similar Pits have been discovered on the Floors of several other Mercurian Craters, such as Beckett and Gibran. These Pits are postulated to have formed when subsurface magma subsided or drained, causing the surface to collapse into the resulting void. If this interpretation is correct, Pit-Floor Craters - such as Picasso - provide evidence of shallow magmatic activity in Mercury's history.
Date Acquired: September 29, 2009
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Resolution: 500 meters/pixel (0,31 miles/pixel)
Scale: the diameter of Picasso is roughly 133 Km (about 83 miles)
Projection: This image is a portion of the NAC approach mosaic from Mercury Fly-By n. 3. It is shown in a simple cylindrical map projection.MareKromium
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ZZ-Mercury-Z1.jpgThe "Face" of Mercury (Natural Colors; credits for the additional process. and color.: NASA/JHU APL/CIW)178 visiteCaption NASA:"On March 17, 2011, the MESSENGER Spacecraft became the first to orbit Mercury, the Solar System's Innermost Planet. This is its first processed color image since entering Mercury orbit. Larger, denser, and with almost twice the Surface Gravity of Earth's moon, Mercury still looks moon-like at first glance.
But in this view its Terrain shows light blue and brown areas near Craters and long bright rays of material streaking the Surface. The prominent bright ray crater Debussy at the upper right is approx. 80 Km (49,68 miles) in diameter. Terrain toward the bottom of the historic image extends to Mercury's South Pole and includes a region not previously imaged from Space".MareKromium
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ZZ-Mercury-Z2.jpgFading away...113 visiteUn piccolo esempio di come la NASA "giochi" con i colori dei Pianeti: nell'inset, come da didascalia, un'immagine in "True Colors" di Mercurio ottenuta dalla Sonda Mariner 10, durante il terzo Fly-By di Mercurio, occorso nel lontano AD 1975. Mercurio, come in TUTTE le foto dell'epoca (incluse quelle ottenute via-telescopio, da Terra) appare di un color rossiccio/marrone, ed infatti più di un Astronomo, in quegli anni, disse che Mercurio era "molto più rosso/arancio di Marte".
Perchè?
Per effetto dell'azione, incessante e combinata, delle particelle cariche che formano il Vento Solare ed i Raggi Cosmici; particelle che, per almeno 4,5/5 miliardi di anni, hanno "martellato" Mercurio (particelle cariche le quali, unite all'azione di bombardamento meteorico, costituiscono l'essenza del cosiddetto "Space Weathering").
Ora, qual'è l'effetto del bombardamento di particelle cariche sulla roccia che forma i Corpi Celesti "massicci" (la roccia che è "esposta" al duro "Ambiente Cosmico", come si dice tecnicamente - Harsh Space Environment)? Semplice: prima la roccia diventa rosa, poi più scura (diciamo arancio/rossiccia), poi ancora più scura (rosso/marrone) ed infine diviene nera. In altre parole: l'azione congiunta delle particelle che formano il Vento Solare (il quale "batte" Mercurio incessantemente e da - relativamente - vicino) e di quelle che formano i Raggi Cosmici, porta la roccia a diventare, negli eoni, sempre più scura.
Questo concetto che Vi ho appena esposto è accettato dall'INTERA Comunità Scientifica.
Ora, come vedete, la NASA ci fa vedere un qualcosa di assolutamente bizzarro, ossia la Superficie di Mercurio che, negli anni tra il 1975 ed il 2011, anzichè rimanere scura (o scurirsi ancor di più) si è "schiarita". E allora? Come è mai possibile una cosa simile? Semplice: non è possibile.
Questo vuol dire che le foto Mariner 10 del 1975 (dal punto di vista cromatico) erano genuine, al pari delle immagini ottenute da Terra. D'altro canto, le foto MESSENGER che ci arrivano adesso sono, sempre dal punto di vista cromatico, "taroccate": per l'esattezza, sono state TUTTE sovrasaturate - ergo sbiadite nei toni cromatici, così "trasformando" Mercurio da Pianeta Rossiccio/Marrone, in Pianeta Grigio.
Perchè? Beh, questo chiedetelo ai Ragazzi di Pasadena: loro, con i colori, ci giocano da parecchi anni....MareKromium
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ZZZ-Mercury-PIA19424.jpg84 visiteCaption NASA:"The MESSENGER Spacecraft sent this frame back to Earth after the it emerged from Superior Solar Conjunction, when the communication is largely blocked by the Sun. This is one of our last views of Mercury from MESSENGER. Featured here is the Ejecta Blanket of a (relatively) fresh Unnamed Impact Crater located just outside the scene. Ejecta scoured the Surface leaving behind beautiful patterns of Secondary Impact Craters".
Date acquired: April 16, 2015
Image Mission Elapsed Time (MET): 71544702
Image ID: 8343072
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 55,67° North
Center Longitude: 97,37° East
Resolution: 19,9 meters/pixel
Scale: This scene is approximately 20 Km acrossMareKromium
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ZZZ-Mercury-PIA19445.jpgReady to say "Farewell"....92 visiteCaption NASA:"This image, acquired on April, 29th, 2015, is one of MESSENGER's last. On April 30th, the Spacecraft will complete its highly successful orbital mission and impact the Surface of Mercury.
Impact was expected at 19:26:02 UTC (3:26:02 pm EDT) but will occur out of sight and communication with the Earth. The MESSENGER Team will try to establish communications with the Spacecraft when its orbit would allow it to be visible from Earth. The inability to establish communications between MESSENGER and the scheduled Earth-based tracking antenna will provide the first confirmation that the Spacecraft has impacted the Surface. After about 30 minutes following the predicted Mercury Impact Time, the Team plans to announce whether MESSENGER's orbital mission has come to an end".
Date acquired: April 29, 2015
Image Mission Elapsed Time (MET): 72595737
Image ID: 8414772
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 69.46° North
Center Longitude: 229,49° East
Resolution: 1,7 meters/pixel
Scale: The largest crater in this image has a diameter of about 330 meters.MareKromium
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ZZZ-Mercury-PIA19448.jpgFarewell Messenger!....127 visiteCaption NASA:"Originally planned to orbit Mercury for one year, the mission exceeded all expectations, lasting for over four years and acquiring extensive datasets with its seven scientific instruments and radio science investigation. This afternoon, the Spacecraft succumbed to the pull of Solar Gravity and impacted Mercury's Surface.
The image shown here is the last one acquired and transmitted back to Earth by the mission. The image is located within the Floor of the roughly 93-Km-diameter Impact Crater named "Jokai". The Spacecraft struck the Planet just north of Shakespeare Basin".
Date acquired: April 30, 2015
Image Mission Elapsed Time (MET): 72716050
Image ID: 8422953
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 72,0° North
Center Longitude: 223,8° East
Resolution: 2,1 meters/pixel
Scale: This image is about 1 Km across
Solar Incidence Angle: 57,9° (meaning that the Sun was 32,1° high on the Local Horizon)
Emission Angle: 56,5°
Phase Angle: 40,7°MareKromium
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