urn:nasa:pds:mgs-rss:data-maps:jgm50c01 1.0 1.22.0.0 Product_Observational 2025 MGS RSS This file contains a digital map of Mars gravity accelerations derived from radio tracking of the Mariner 9 and Viking Orbiter Spacecraft. The map is vertical gravity in milligals. There are no Mars Global Surveyor data included in this model. This is considered to be the baseline (pre-MGS) Mars model for the JPL Gravity Science Team. These data cover 1971-11-14T00:00:00Z to 1980-08-07T23:59:59Z. William Sjogren 1 Jet Propulsion Laboratory https://ror.org/027k65916 2025-02-18 1.0 This product, JGM50C01.IMG, was originally released as part of the PDS3 MGS-M-RSS-5-SDP-V1.0 data set. The metadata have been migrated to PDS4. The keywords WESTERNMOST_LONGITUDE,EASTERNMOST_LONGITUDE, MINIMUM_LATITUDE, and MAXIMUM_LATITUDE. As used in radio science products, these are the extreme values at pixel centers rather than the extremes of the area represented. For example, if the image has 180 rows at equally spaced latitudes (-89.5, -88.5, ..., -0.5, +0.5, ..., +89.5) then MINIMUM_LATITUDE = -89.5 and MAXIMUM_LATITUDE = 89.5 A more conventional usage might have these same keywords set to -90.0 and +90.0, respectively, because those are the limits of the area represented by the pixels. In cases where the radio science image has 181 rows (-90.0, -89.0, ...,-1.0, 0.0, +1.0, ..., +90.0), the radio science label would show MINIMUM_LATITUDE = -90.0 and MAXIMUM_LATITUDE = 90.0 The more conventional label, in this case, would have the same values. 1971-11-14T00:00:00Z 1980-08-07T23:59:59Z Science Derived Mars Global Surveyor Gravity Anomaly Maps Data Mars Global Surveyor Mission urn:nasa:pds:context:investigation:mission.mars_global_surveyor data_to_investigation Mariner 9 Host urn:nasa:pds:context:instrument_host:spacecraft.mr9 is_instrument_host Viking Orbiter 1 Host urn:nasa:pds:context:instrument_host:spacecraft.vo1 is_instrument_host Viking Orbiter 2 Host urn:nasa:pds:context:instrument_host:spacecraft.vo2 is_instrument_host Radio Science Subsystem (RSS) Instrument urn:nasa:pds:context:instrument:rss.mr9 is_instrument Radio Science Subsystem (RSS) Instrument urn:nasa:pds:context:instrument:rss.vo1 is_instrument Radio Science Subsystem (RSS) Instrument urn:nasa:pds:context:instrument:rss.vo2 is_instrument Mars Planet urn:nasa:pds:context:target:planet.mars data_to_target Array_3D_Image cartography_parameters_to_image_object -179.5 179.5 89.5 -89.5 Equirectangular 0 0 0 Coordinate Pair 59110.0455857414781 59274.6975233062185 1.00278551532033422 1 -10669445.5541951191 5334722.77709755953 Planetocentric Baseline (Pre-MGS) Mars 3396190 3396190 3396190 Positive East Array_3D_Image display_settings_to_array Sample Left to Right Line Top to Bottom MGS-M-RSS-5-SDP-V1.0:MARS50C.A01:JGM50C01.IMG data_to_derived_source_product 10.17189/1519757 PDS Planetary Plasma Interactions Node This is the first version converted to PDS4. The DOI references the source PDS3 data set. JGM50C01.IMG 1998-12-22T16:38:20 518400 345ea40a5239ca970bbdddef8d3bbcf8 Array_3D_Image 0 3 Last Index Fastest Each point gives the Mars gravity anomaly in milligals, which is the difference of the model gravity on the geoid from the normal gravity on a reference ellipsoid with semi-major-axis = 3397.0 km, GM = 42828.35796 km**3/s**2, flattening = 5.079304192e-3, and rotation rate = 7.088218081e-5 rad/s. IEEE754MSBDouble mm/s/s Band 1 1 Line 180 2 Sample 360 3 -3.40282265508890445e+38 The Digital Map contains values of vertical gravity in milligals (1 milligal = 0.01 mm/s/s). The true values can be obtained by multiplying the sample in the map by SCALING_FACTOR and then adding OFFSET.