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ZZ-ZZ-ZZ-ZZ-ZZ-FastWalker-konig080896.gifFast-walker in transit90 visiteMappa dei dettagli riconoscibili della superficie Lunare:
1. Mercator
2. Konig
3. Agatharchides
4. Hippalus
5. Cape Kelvin
6. Campanus
Nota: i Curatori del Sito LUNASCAN PROJECT, nel commentare questo straordinario filmato, ritengono che quanto ripreso sia l'OGGETTO EFFETTIVO "in transito" e NON la sua OMBRA che passa sulla superficie lunare. Si tratta, come ovvio, di una opinione rispettabilissima, ma che noi ci sentiamo di non condividere.
Cogliamo l’occasione – fornitaci dalle interessanti ed acute riflessioni svolte dal nostro Amico e Socio “Anakin” in sede di commento al frame – per fare qualche precisazione sul motivo per cui noi abbiamo optato per l’ipotesi che vuole la ripresa di un’“ombra” in transito sulla Superficie Lunare e non la ripresa dell’oggetto che la crea.
Allora: tralasciando la “sensibilità” dell’Osservatore (un dato troppo soggettivo per avere una effettiva rilevanza in questa sede), diciamo che, quando si usa un telescopio, si dispone di una serie di oculari i quali determinano il “livello di ingrandimento” del target osservato.
Ora noi sappiamo che esistono non solo oculari grandi e piccoli ma anche – ed ovviamente – oculari più potenti (e cioè che ingrandiscono di più) ed oculari meno potenti (e cioè che ingrandiscono di meno).
Quanto più un oculare è "potente", tanto più – di regola – la qualità dell’immagine si abbassa e tanto più il campo visivo (l’ampiezza della superficie osservata) si restringe.
Questo particolare, in ipotesi di osservazione di stelle, nebulose o pianeti (da Mercurio a Plutone), può apparire irrilevante (anche se un oculare “forte” può di fatto “risolvere” un Sistema Stellare Multiplo, ad esempio), ma nel caso di osservazione della Luna (un oggetto davvero vicino) esso diventa decisivo.
Perché? Perchè osservando la Luna con un oculare - ad es. - di 4 mm (il quale produce un notevolissimo ingrandimento del target), potremmo riuscire a vedere, in ipotesi di passaggio di un oggetto nei pressi della sua superficie, O l'oggetto, O l’ombra che esso proietta, ma MOLTO difficilmente riusciremmo a vedere entrambi.
Non dimentichiamo, poi, altri due fattori critici: l’altezza del Sole rispetto alla Regione Lunare ripresa (ed è questa altezza che determina la posizione di un’ombra rispetto all’oggetto che la produce) ed il cosiddetto Angolo di Fase e cioè l’angolo descritto – in questo caso – dal Sole, l’Oggetto (ergo anche la Luna) e l’Osservatore (ergo anche la Terra).
Ora l’Angolo di Fase implica e determina (fra l’altro) una Prospettiva di Osservazione la quale, come le immagini degli Anelli di Saturno (e dei loro dettagli) ottenuti dalla Sonda CASSINI-HUYGENS ci insegnano, cambia radicalmente la visuale dell’obbiettivo DAL PUNTO DI VISTA dell’Osservatore.
Tutto ciò premesso, per vedere sia l’Oggetto, sia l’Ombra da esso proiettata al suolo, si sarebbero dovute determinare (congiuntamente), a nostro parere, almeno queste condizioni:
1) uso di un obbiettivo telescopico a potenza bassa (o addirittura di tipo grandangolare);
2) passaggio dell’oggetto a “volo radente” (o, in alternativa, passaggio dell’oggetto sulla perpendicolare dell’Osservatore);
3) Sole allo Zenith (o nei suoi pressi) della Regione Lunare ripresa (o, se si preferisce, Angolo di Fase Basso - diremmo <25°).
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ZZ-ZZ-ZZ-ZZ-ZZ-Gamma-Ray Moon.jpgGamma Ray Moon123 visiteDa "NASA - Picture of the Day" del 27 Maggio 2006:"If you could see Gamma Rays - photons with a million or more times the energy of visible light - the Moon would appear brighter than the Sun! The startling notion is demonstrated by this image of the Moon from the Energetic Gamma Ray Experiment Telescope (EGRET) in orbit on NASA's Compton Gamma Ray Observatory from April 1991 to June 2000. Then, the most sensitive instrument of its kind, even EGRET could not see the quiet Sun which is extremely faint at gamma-ray energies. So why is the Moon bright? High energy charged particles, known as cosmic rays, constantly bombard the unprotected lunar surface generating gamma-ray photons. EGRET's Gamma-Ray vision was not sharp enough to resolve a lunar disk or any surface features, but its sensitivity reveals the induced gamma-ray moonglow. So far unique, the image was generated from eight exposures made during 1991-1994 and covers a roughly 40° wide field of view with gamma-ray intensity represented in false colors".
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ZZ-ZZ-ZZ-ZZ-ZZ-Lunar South Pole.jpgNo "Lunar Ice" at the South Pole...64 visite"...a new radar survey of the Moon’s Southern Pole has cast doubt on the hope that there might be accessible deposits of water ice in permanently dark craters. This new survey, performed with the Arecibo Observatory in Puerto Rico, found elevated Hydrogen levels in regions of bright sunlight - not just inside the shadowed walls of craters. It seems that scattered rocks associated with impact craters have given previous instruments a false reading...".
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ZZ-ZZ-ZZ-ZZ-ZZ-LunarRedFlash_seip_f.jpgA "red flash" on the Moon132 visiteDa "NASA - Picture of the Day", del 22 Settembre 2005:"This remarkable telescopic image highlights the deep orange cast of a waning gibbous Moon seen very close to the eastern horizon on September 19. In fact, today's equinox at 22:23 UT marks the beginning of Fall in the Northern Hemisphere and makes this view from Stuttgart, Germany an almost Autumn Moon. While the long sight-line through the atmosphere filters and reddens the moonlight, it also bends different colors of light through slightly different angles, producing noticeable red (bottom) and green (top) lunar rims. Also captured here floating just below the Moon is a thin, red mirage (inset) - in this case, an atmospherically magnified and distorted image of the red rim. Of course, this tantalizing lunar 'red flash' is related to the more commonly seen 'green flash' of the Sun".
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ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-CTX_Moon_6Oct2004.jpgThe Moon from Mars Reconnaissance Orbiter129 visiteThis image of Earth's moon was acquired by the Mars Reconnaissance Orbiter (MRO) Context Imager (CTX) camera during calibration and testing between 2:00 and 3:00 a.m. Pacific Daylight Time (PDT) on 6 October 2004. The image was taken by CTX before it was delivered and mounted on the MRO spacecraft. It was obtained from the parking lot at the Malin Space Science Systems facility in San Diego, California. In this image, east is toward the top and south is toward the bottom. The image demonstrates the field of view of the MRO CTX camera, which is 5064 pixels across (clicking on the image above will permit download of the full 5064 pixels-wide image). When in its circular mapping orbit about Mars, the 5064 pixels will cover a swath that is about 30 kilometers (~18.6 miles) across. CTX will obtain its 30 km-wide images at a resolution of about 6 meters (~19.7 feet) per pixel. CTX images will be used to provide context for the very high resolution images (better than 1 meter per pixel) to be obtained by the MRO HiRISE camera. CTX data will also provide context for MRO's CRISM infrared imaging spectrometer as well as provide detailed observations of martian landforms and potential, future Mars landing sites.
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ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-The Moon.jpgThe North Pole of the Moon68 visiteCaption NASA originale:"This arresting image of the third quarter Moon in the excellent skies above the Pine Crest Farm Observatory, Dell Prairie, Wisconsin, was recorded with a 24" telescope and digital camera on October 19, 2000. Marvelously detailed, especially along the terminator or shadow line between lunar night and day, this cropped version of the full mosaicked image shows the cratered North Polar Region and the broad smooth Mare Imbrium. Notable at the northern edge of the Mare Imbrium (Sea of Rains) is the 95 Km wide dark crater Plato, while the dramatic straight "cut" to the right of Plato, (toward the terminator) is the Vallis Alpes (Alpine Valley). The long, graceful arc of the lunar Montes Apenninus in the lower portion of the image sweeps Southward along the boundary of the mare toward the left and ends near the bright ray crater Copernicus at the picture's edge. In 1971, Apollo 15 landed near the gap beyond the opposite (northern) end of the Montes Apenninus arc".
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ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-Earth&Moon from Nozomi.jpgThe Earth-Moon System from Nozomi69 visiteCaption NASA originale:"Japan launched its first mission to orbit Mars, Nozomi (Hope), on July 3rd, 1998, from the Kagoshima Space Center on the island of Kyushu. Nozomi's goal is to explore the Martian atmosphere and magnetic field as well as Regions of the Planet's surface and Moons. Formerly known as Planet-B, the spacecraft will use highly elliptical orbits with successive Earth/Moon flybys to help slingshot itself along its ultimate trajectory toward Mars, arriving at the Red Planet in October 1999. This stunning picture of the crescent Earth-Moon system was taken by Nozomi's onboard camera on July 18 from a point in space about 100.000 miles from the Earth and 320.000 miles from the Moon. Vibrant and bright, the reflective clouds and oceans of Earth contrast strongly with the dark, somber tones of the Lunar Surface".
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ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-The Moon-1.jpgThe Moon from Galileo73 visiteCaption NASA originale:"The Moon's surface is covered with craters, scars of frequent impacts during the early history of the Solar System. Now, recent results from the Lunar Prospector spacecraft support the idea that the Moon itself formed from the debris of a giant impact of a Mars-sized planetary body with the Earth nearly 4,5 BY ago. The impact theory of lunar origin can explain why Moon rocks returned by the Apollo missions have the same isotopic ratios as Earth rocks while the Moon seems deficient in heavy elements like iron. It can also explain a critical finding of the Lunar Prospector experiments - that the Moon's core is proportionally very small. If the Moon formed simply as a Sister World, its origin paralleling Earth's formation from the primordial Solar Nebula, it should have similar iron content and relative core size. But material blasted from the surface of Earth by an impacting body would lack the iron and heavy elements which had settled to the Earth's core yet retain similar ratios of chemical isotopes. A fraction of this debris cloud would remain in Earth orbit ultimately forming the Moon".
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ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-ZZ-The Moon.jpgMare Imbrium, from Galileo73 visiteCaption NASA originale:"Checking out the Galileo spacecraft's cameras during its December 1992 fly-by of Earth's Moon, controllers took this dramatically illuminated picture through a violet filter. The view looks down on the Moon's North Polar Region with the Sun shining from the left at a low angle and the direction toward the Moon's North Pole toward the lower right.
Across the image upper left stretches the smooth volcanic plain of the Mare Imbrium. Pythagoras crater, 65 miles wide, is near the center of the image -- mostly in shadow, its central peak just catches the sunlight (...)".
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