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SpaceWaterfall.jpgOrion's Waterfall (NGC 1999 and HH Objects 222 and 401)58 visite"...Non duce Tempus eget..."
(Lucano)
"...Il Tempo non ha bisogno di qualcuno che lo guidi..." (trad. libera)MareKromium
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PSP_007653_2010_RED_abrowse-00.jpgBright on Dark (MULTISPECTRUM; credits: Lunexit)58 visiteThis image reveals bright Slope Streaks in Bahram Vallis, a long sinuous valley that winds across North-Eastern Lunae Planum and Xanthe Terra to the circum-Chyrse basin.
Typically, dark and light-toned Slope Streaks appear together on light-toned slopes. This scene is a rare case in which only bright streaks are visible on a dark surface. Slope Streaks generally start at a point source and widen downslope as a single streak or branch into multiple streaks. Some of the Slope Streaks show evidence that downslope movement is being diverted around obstacles, such as large boulders, and a few appear to originate at boulders or clumps of rocky material.
Many hypotheses have been proposed for the formation of slope streaks including dry avalanching, geochemical weathering, liquid stains or flows, and moisture wickering. Recent observations from HiRISE images have revealed that the interior of Slope Streaks is lower in elevation than the surroundings indicating that material must have been removed and then deposited in the formation of the streak.
Slope Streak formation is among the few known processes currently active on Mars. Where they appear together, dark Slope Streaks cross cut and lie on top of the older and lighter-toned streaks leading to the belief that lighter-toned streaks are dark streaks that have lightened with time as new dust settled on their surface. Over the course of several years, MOC images from this Region did not reveal any new dark or light-toned Slope Streaks suggesting that streak formation is not currently active here.
HiRISE will continue to monitor this Region for new slope streaks and changes in tone of old streaks.MareKromium
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PrometheiPlanum.jpgPromethei Terra (Natural Colors + MULTISPECTRUM; credits: ESA & Lunexit)58 visitePromethei Planum, an area seasonally covered with layer of ice more than 3500 mt thick layer of ice in the Martian South Polar Region, was the subject of the High Resolution Stereo Camera’s focus on 22 September 2005 as Mars Express was in orbit above the Red Planet.
Promethei Planum lies at approx. 76° South Lat. and 105° East Long.
An approx. 100 Km-large and 800 mt-deep impact crater is visible in the Northern part of the image. The crater’s interior is partly covered in ice.
In the centre of the image are structures that may have been created by basaltic lava flow from a volcano. This area is covered in ice. The dark dunes towards the bottom of the image are most likely made up of dust originating from this lava flow or volcanic ash.
A broad sheet of ice, which is an extension of the South Polar Ice Cap is located South of the lava flow. The steep flanks clearly show white, clean ice. The thickness of the ice is between 900 and 1100 mt.MareKromium
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HD-189733b-PIA10364.jpgHD-189733b - Exoplanet in Vulpecula58 visite"...Vulpes non capitur muneribus..."
(Proverbio Medioevale)
"...L'astuzia non si lascia vincere (non la si può corrompere) dai (con) regali..." (trad. libera)MareKromium
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HD-189733b.jpgHD-189733b - Exoplanet in Vulpecula58 visite"...Saepe condita luporum fiunt rapinae vulpium..."
(Proverbio Medioevale)
"...Sovente le volpi riescono a sottrarre anche le prede nascoste dai lupi..." (trad. libera)MareKromium
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SOL236.jpgEvening Shadow... - Sol 236 (natural colors + MULTISPECTRUM; credits: Dr M. Faccin & Lunexit)58 visitenessun commentoMareKromium
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NGC-2808-The_Region.jpgLooking towards the Centaurus Region58 visite"...Vetera extollimus, recentium incuriosi..."
(Tacito)
"...Magnifichiamo l'antichità e trascuriamo l'attualità..."MareKromium
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NGC-2808-1.jpgNGC 2808 - Omega Centauri (Globular Star Cluster)58 visite"...In culpa est animus, qui se non effugit unquam..."
(Orazio)
"...Un animo consapevole non può sfuggire a se stesso..." (trad. libera)
Nota per i Lettori: ho tradotto "in culpa" come se stesse a significare "nella consapevolezza". Non è una svista, ma una semplice interpretazione personale.MareKromium
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Craters-Pollack_Crater-H1201_0001_ND3_crop_wide-0.jpgPollack Crater and "White Rock" (RAW Frame; credits: ESA - Mars Express)58 visitenessun commentoMareKromium
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O-Mariner9-72-Pollack_Crater_and_White-Rock.jpgPollack Crater and "White Rock" from Mariner 9 (RAW Frame - credits: NASA)58 visite"...It was interesting to browse through the Mariner 9 data set to locate these images, because evidently the Mariner 9 Team wasn't sure to make of these strange bright deposits.
The first one I posted was described as "white rock" in a comment on the image, and that name has stuck. But another image's descriptive comment read "curious ice patches".
Another totally misidentified not only the nature but the location of the photo, describing it as "Polar Cap".
Comments on images of other places in the Mariner 9 Catalog generally reflect the fact that Mars had not yet been systematically surveyed by an orbiter, so the scientists often weren't quite sure what they were looking at, and even when it was clear there were craters, those craters had mostly not yet been named.
I came across comments like "peculiar filametary structure" and "possible craters" and "streaky detail" and "cloud?" and "multitude of surface detail" and "odd fork-shaped bright pattern."
It's fun to browse through that table and imagine surveying Mars, with a spacecraft stationed at the Planet for the first time, made all the more dramatic by its initial obscuration by a dust storm that slowly cleared.
Mariner 9 is one of the more challenging data sets to work with because it's just so old. However, everything you need to access it, find images, view them, and convert them to more familiar formats is readily available online. First of all, the data itself can be found by browsing the data volumes at the PDS Imaging Node, and you can learn a little bit about the data at the National Space Science Data Center. To figure out what's what and to try to track down images of specific areas, you can download this spreadsheet (XLS format, zipped, 7.5 MB) containing an index to all the images.
The images are all in a format that won't be familiar to most of you, but like most spacecraft data you can convert a folder full of images to PNG format using my favorite amateur-produced software, Björn Jónsson's IMG2PNG. However, if you're only working with a couple of images, I'd recommend a different amateur-produced piece of software for converting the images, Piotr Masek's MarinerView, because MarinerView can be used to correct the Mariner 9 images (one at a time) for the little white specks of noise that are spattered across every one.
I'm slowly working on tracking down images of "White Rock" taken by every mission. First Mariner 9, then the Viking orbiters, then Mars Global Surveyor's MOC, then Mars Odyssey THEMIS, then Mars Express HRSC, and, finally, I should be able to produce Mars Reconnaissance Orbiter views from three different instruments: HiRISE, CTX, and CRISM. Stay tuned for further installments...".
Emily Lakdawalla (Planetary Society)MareKromium
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SOL1008-MIC-01.jpgPebbles in the "wet" (?) Martian Sand... - Sol 1008 (True Colors; credits: Dr M. Faccin)58 visiteUn altro SPLENDIDO Lavoro del Dr Faccin, che ci porta - a nostro parere - ancora un pò più vicini alla realtà di Marte. Una realtà che, per innumerevoli motivi e colpe (anche nostre, ovviamente), se ne sta ancora "sotto la sabbia" del Pianeta più famoso del Sistema Solare...
Ma, come vedete bene in questo frame, piano-piano, stiamo "smuovendo" quella sabbia (ci viene da dire "palesemente umida"...) sotto la quale, forse, si cela una grandissima Sorpresa...
Comunque, diamo tempo al Tempo, et procedemus!...MareKromium
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OPP-SOL569-1.jpgRover Tracks and Martian Paving - Sol 569 (True Colors + MULTISPECTRUM; credits: Dr G. Barca & Lunexit)58 visitenessun commentoMareKromium
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