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The Magellan spacecraft has been collecting Doppler radio tracking data on the gravity field of Venus since completing radar mapping in 1992 After Magellan's successful aerobaking in August 1993, high resolution gravity data were acquired over the high latitude regions, providing relatively uniform global coverage with feature resolution between 200 kilometers and 400 kilometers and a sensitivity of I to 5 milligals (100 milligals equals I millimeter per second squared) By recording slight varations in the spacecraft's orbit as it passes over Venusian mountain belts, volcanoes and valleys, scientists are able to construct a "picture" of the distribution of density variations in the planet's interior. Those density differences are shown as color hues on this global image of Venus (red is high, blue is low). The globe is centered at 30 degrees west longitude and has been tipped forward by 30 degrees to better display the gravity differences in the Ishtar and Maxwell regions Slight differences in the gravity field provide clues about the geological processes responsible for shaping features observed at the surface The surface topography is displayed as three dimensional highs and lows on this image. The surface topography has been exaggerated by a factor of 100 to emphasize variations in elevation. It is evident that there is significant correlation of gravity with topography Maxwell Montes appears as a yellow and red area near the top right of the globe. Maxwell is the highest region of the planet and is of critical importance to geophysicists who must know the gravity field to make realistic inferences about the planet's internal structure. The high mountains of Beta Regio (left center) are shown in red. The topographic lows occur in the same regions where the dark blue color indicates that the gravity is low #####
Description
The Magellan spacecraft has been collecting Doppler radio tracking data on the gravity field of Venus since completing radar mapping in 1992 After Magellan's successful aerobaking in August 1993, high resolution gravity data were acquired over the high latitude regions, providing relatively uniform global coverage with feature resolution between 200 kilometers and 400 kilometers and a sensitivity of I to 5 milligals (100 milligals equals I millimeter per second squared) By recording slight varations in the spacecraft's orbit as it passes over Venusian mountain belts, volcanoes and valleys, scientists are able to construct a "picture" of the distribution of density variations in the planet's interior. Those density differences are shown as color hues on this global image of Venus (red is high, blue is low). The globe is centered at 30 degrees west longitude and has been tipped forward by 30 degrees to better display the gravity differences in the Ishtar and Maxwell regions Slight differences in the gravity field provide clues about the geological processes responsible for shaping features observed at the surface The surface topography is displayed as three dimensional highs and lows on this image. The surface topography has been exaggerated by a factor of 100 to emphasize variations in elevation. It is evident that there is significant correlation of gravity with topography Maxwell Montes appears as a yellow and red area near the top right of the globe. Maxwell is the highest region of the planet and is of critical importance to geophysicists who must know the gravity field to make realistic inferences about the planet's internal structure. The high mountains of Beta Regio (left center) are shown in red. The topographic lows occur in the same regions where the dark blue color indicates that the gravity is low #####
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