google.com, pub-0288379932320714, DIRECT, f08c47fec0942fa0 GRAVIR LES MONTAGNES... EN PEINTURE: PAVONIS MONS BY NASA MARS GLOBAL SURVEYOR

Wednesday, April 4, 2018

PAVONIS MONS BY NASA MARS GLOBAL SURVEYOR







 NASA MARS GLOBAL SURVEYOR  (1996-2007), 
Pavonis Mons (14,000m / 14km - 46,000ft / 8,7 mi) 
MARS

The mountain 
Pavonis Mons (14,000m / 14km - 46,000ft / 8,7 mi)  latin for "peacock mountain" is a large shield volcano located in the Tharsis region of the planet Mars. It is the middle member of a chain of three volcanic mountains (collectively known as the Tharsis Montes) that straddle the Martian equator between longitudes 235°E and 259°E. The volcano was discovered by the Mariner 9 spacecraft in 1971 and was originally called Middle Spot. Its name formally became Pavonis Mons in 1973.
Using NASA Mars Global Surveyor  and Odyssey data, combined with developments in the study of glaciers, scientists suggest that glaciers once existed on Pavonis Mons and probably still do to some extent.  Evidence for this includes concentric ridges (moraines "dropped" by glaciers), a knobby area (caused by ice sublimating), and a smooth section that flows over other deposits (debris-covered glacial ice). The ice could have been deposited when the tilt of Mars changed the climate, thereby causing more moisture to be present in the atmosphere. Studies suggest the glaciation happened in the Late Amazonian period, the most recent period in Mars chronology. Multiple stages of glaciation probably occurred. The ice present today represents one more resource for possible future colonization of the planet.

The mission
Mars Global Surveyor (MGS) was an American robotic spacecraft developed by NASA's Jet Propulsion Laboratory and launched November 7, 1996. Mars Global Surveyor was a global mapping mission that examined the entire planet, from the ionosphere down through the atmosphere to the surface.  As part of the larger Mars Exploration Program, Mars Global Surveyor performed monitoring relay for sister orbiters during aerobraking, and it helped Mars rovers and lander missions by identifying potential landing sites and relaying surface telemetry.
It completed its primary mission in January 2001 and was in its third extended mission phase when, on 2 November 2006, the spacecraft failed to respond to messages and commands. A faint signal was detected three days later which indicated that it had gone into safe mode. Attempts to recontact the spacecraft and resolve the problem failed, and NASA officially ended the mission in January 2007.
The Mars Orbiter Camera (MOC) science investigation used 3 instruments: a narrow angle camera that took (black-and-white) high resolution images (usually 1.5 to 12 m per pixel) and red and blue wide angle pictures for context (240 m per pixel) and daily global imaging (7.5 km per pixel). MOC returned more than 240,000 images spanning portions of 4.8 Martian years, from September 1997 and November 2006.[6] A high resolution image from MOC covers a distance of either 1.5 or 3.1 km long. Often, a picture will be smaller than this because it has been cut to just show a certain feature. These high resolution images may cover features 3 to 10 km long. When a high resolution image is taken, a context image is taken as well. The context image shows the image footprint of the high resolution picture. Context images are typically 115.2 km square with 240 m/pixel resolution.