Mars Reconnaissance Orbiter (MRO)
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ESP_014083_0945_RED_abrowse-02.jpgActive Geyser on Mars: the "Mouth" (Natural Colors; credits: Dr M. Faccin & Lunexit)54 visitenessun commentoMareKromium
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ESP_014097_1120_RED_abrowse.jpgDisappearing Craters (Natural Colors; credits: Lunar Explorer Italia)54 visiteImpact Craters that form at High Latitudes often disappear faster than those that form in Equatorial Regions. The craters in this image are only barely detectable.
Over time, craters in ice, particularly large craters, "relax".
Their depth-to-diameter ratio decreases as the bowl of the crater gets shallower with time. The craters slowly appear softer and smoother, fading into the surrounding landscape, until they remain only as circular patterns on flat ground, before they eventually disappear altogether. The larger the crater, the faster it will relax.
The reason for the crater degradation is partly due to in-filling by snow or dust and slumping off of the crater walls, and also partly from processes that produce the patterned ground you see in this HiRISE image. But the primary reason for the shallowing is because the ground at High Latitudes on Mars is ice-rich, and ice is not very strong. At warmer temperatures found in the Inner Solar System, ice generally flows more easily than rock, so ice cannot support the structure of the crater as well as rock. The crater relaxes as the ice begins to flow back to a level surface.
All of the processes listed above have likely acted on these craters, and recently, they have also been swept by Dust Devils, which left dark streaks in their wake.MareKromium
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ESP_014100_1600_RED_abrowse.jpgPossible Inverted Meanders (Natural - but enhanced - Colors; credits: Lunexit)54 visitenessun commentoMareKromium
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ESP_014103_2485-ESP_014393_2485.jpgLook who's there: the Phoenix Lander! (Natural Colors; credits: Lunexit)54 visiteThe High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter captured Winter images of NASA's Phoenix Mars Lander surrounded by dry-ice frost on Mars.
As the Sun began to reappear on the horizon following the deepest, darkest days of North Polar Winter on Mars, the HiRISE camera imaged the Phoenix Landing Site on July 30, 2009, (left image) and in Aug. 22, 2009 (right).
The Sun was only 1° above the Local Horizon when the July image was taken at approximately 14:00 M.L.T. .-
In the August image the Sun was 6° above the L.H. when the image was taken, at about 13:44 M.L.T. .
By matching up the images with the known location of the Lander, the HiRISE team identified the hardware, disguised by frost, despite the fact that the views were hindered by poor lighting and atmospheric haze, which often obscures the Martian Surface at this location and season.
Carbon Dioxide frost completely blankets the Surface in both images. The amount of brightness doesn't necessarily indicate the amount of frost seen in the image because of the way the images are processed to produce optical contrast. Each of these images is stretched differently for optimal contrast, so "bright" and "dark" can't be compared directly between images without doing complex calibrations. In fact, if you stretched all of them exactly the same, the darker areas in the frost covered images are still brighter than typical soil, like that surrounding the Lander in the frost-free image.
Other factors affect the relative brightness, such as the size of individual grains of CO2 ice, the amount of dust mixed in with the ice, the amount of sunlight hitting the Surface, and different lighting angles and slopes. The winds are also changing direction and strength, moving loose frost and dust around over time.
Studying these changes will help scientists understand the nature of the seasonal frost and Winter Weather Patterns in this area of Mars.
The amount of CO2 frost is increasing as late Winter transitions to early Spring, so the layer of frost is getting thicker in each image, slowly encasing the Lander. The maximum thickness was expected to be on the order of tens of centimeters, which would have reached its peak in September 2009. The thickness has not been confirmed yet because the MRO Spacecraft suspended taking images when it entered safe mode on August 26.
Oct. 26, 2009, marked the first day of Spring in the Northern Hemisphere of Mars.
The Planetary Society has put together an animation comparing the hardware at different times. (see ---> http://www.planetary.org/blog/article/00002182/).
The Phoenix Mars Lander ceased communications last November (2008), after successfully completing its mission and returning unprecedented science data to Earth. Launched Aug. 4, 2007, Phoenix safely touched down on Mars on May 25, 2008, at a site farther North than where any previous Spacecraft had landed. During the first quarter of 2010, teams at JPL will listen to see if Phoenix is still able to communicate with Earth. Springtime thaw images may also be available.
These views are a portion of a HiRISE image which is available in full-frame at http://hirise.lpl.arizona.edu/ESP_014393_2485.
MareKromium
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ESP_014103_2485_RED_abrowse.jpgMonitoring of Phoenix Landing Site (Natural Colors; credits: Lunexit)54 visitenessun commentoMareKromium
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ESP_014111_1130_RED_abrowse.jpgPityhusa Patera Caldera (Natural Colors; credits: Lunexit)54 visitenessun commentoMareKromium
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ESP_014114_0935_RED_abrowse.jpgSouth Polar Residual Cap Monitoring (Natural Colors; credits: Lunexit)54 visitenessun commentoMareKromium
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ESP_014123_0930_RED_abrowse.jpgDry Ice (Natural Colors; credits: Lunexit)57 visitenessun commentoMareKromium
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ESP_014124_1975_RED_abrowse.jpgSinuous Channel in Arabia Terra (Natural Colors; credits: Lunexit)54 visitenessun commentoMareKromium
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ESP_014126_2120_RED_abrowse.jpgNorthern Crater with Windstreak (Natural Colors; credits: Lunexit)54 visitenessun commentoMareKromium
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ESP_014139_2070_RED_abrowse-00.jpgPhyllosilicates Deposit North Mawrth Vallis (Natural Colors)58 visitenessun commentoMareKromium
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ESP_014139_2070_RED_abrowse-01.jpgFumes, North of Mawrth Vallis (Natural Colors; credits: Dr M. Faccin)105 visiteUna splendida ed affascinante (nonchè ECCEZIONALE) visione di "fumi" che si sollevano da una regione di modeste dimensioni situata a Nord della famosa Mawrth Vallis. La scoperta - perchè di scoperta si tratta - è del nostro Marco Faccin; la NASA, purtroppo, sebbene da noi sollecitata al riguardo, non ha - evidentemente... - ancora trovato il tempo di rispondere e di darci qualche delucidazione su quello che staremmo guardando.
Il dettaglio in oggetto non è assolutamente visibile/distinguibile osservando il full-frame MRO in formato JPEG, ma bisogna aprire il file in JP2 e "mettersi a cercare".
I "fumi" che vedete in questa colorizzazione (fatta al TOP delle nostre possibilità, miscelando la tecnica di colorizzazione in Colori Naturali STD con la Tecnica MULTISPECTRUM) sono stati da noi identificati come tali (e NON, quindi, come nebbie) in quanto riteniamo di aver individuato i punti esatti di emanazione.
Lo spettacolo che stiamo osservando, quindi ed a nostro parere, potrebbe costituire l'evidenza oggettiva di una Caldera Attiva (simile, concettualmente, alle cosiddette "Solfatare" di Pozzuoli - NA).
Morale: Marte è tutt'altro che morto...MareKromium
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