This simply beautiful view (that was obtained by combining information coming from two different instruments located onboard the NASA - Mars Reconnaissance Orbiter) has the purpose to map (however, in an approximate way) the Main (---> Basic) Composition of the Ground existing in a small portion of the Nili Fossae Plains Region, which is located in the Martian Northern Hemisphere. This specific Site, is part of the largest known Carbonate-rich Deposits of Mars. In this view (that has been converted in Absolute Natural Colors), the orange/brown Surface indicates a Carbonate-rich Composition, the white/orange Ripples indicate that they are made of Olivine-rich Sands, and the gray areas indicate a Basaltic Composition. The Carbon Dioxide from the Atmosphere existing on the "early" (---> extremely ancient) Mars, reacted with the Surface Rocks and formed Carbonates, thus thinning the Atmosphere by "sequestering" (---> taking away) the Carbon that was present in the Rocks themselves. An analysis of the amount of Carbon contained in the Plains of Nili Fossae estimated the total at no more than twice the amount of Carbon existing in the "Modern" Atmosphere of Mars, which is mostly made of Carbon Dioxide ("CO2"). Said amount of Carbon, however, even though is much more than the one contained in all the other known Carbonate-rich Regions of Mars, is still far too small to explain how Mars could have had, in a remote past, a thick enough Atmosphere that was fit to keep (---> preserve) its Surface Waters from freezing during a (most likely VERY long) period when Rivers were cutting extensive Valley Networks on the Red Planet. Other possible explanations for the change from an Era with Rivers to the extremely dry Mars of today are still being investigated. This image covers an area approximately 1,4 miles (such as about 2,253 Km) wide. The Scale Bar indicates 500 meters (such as 1640 feet). The full extent of the Carbonate-containing Deposits found in the Region is - at least - as large as Delaware and, perhaps, as large as Arizona. Mars Local Time: 14:10 (Early Afternoon) This picture (which is an original NASA - Original Mars Reconnaissance Orbiter Falsely Colored and NON-Map-Projected Sub-frame identified by the serial n. ESP_032873_2020-1) has been additionally processed, extra-magnified to allow the Readers a better view of the details, contrast enhanced, Gamma corrected, 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 - Mars Reconnaissance Orbiter and then looked down, towards the Surface of Mars), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. |