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<Product_Observational
   xmlns="http://pds.nasa.gov/pds4/pds/v1"
   xmlns:pds="http://pds.nasa.gov/pds4/pds/v1"
   xmlns:cart="http://pds.nasa.gov/pds4/cart/v1"
   xmlns:disp="http://pds.nasa.gov/pds4/disp/v1"
   xmlns:geom="http://pds.nasa.gov/pds4/geom/v1"
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     ">
    <Identification_Area>
        <logical_identifier>urn:nasa:pds:mgs-rss:data-maps:ggm0964a</logical_identifier> 
        <version_id>1.0</version_id>
        <title>MGS Digital Map of the Mars Gravity Anamolies for the MGM0964C18 Model to 50x50</title>      
        <information_model_version>1.22.0.0</information_model_version> 
        <product_class>Product_Observational</product_class>
        <Citation_Information>
            <publication_year>2025</publication_year> 
            <keyword>MGS</keyword>
            <keyword>RSS</keyword>
            <description> 
                This file contains a digital map of Mars gravity anomalies evaluated
                for the MGM0964C18 model to 50x50 from the Mars Global Surveyor. These 
                data cover 1997-09-12T00:00:00Z to 1999-03-27T23:59:59Z.
            </description>
            <List_Author>
               <Person>
                    <given_name>David</given_name>
                    <family_name>Smith</family_name>
                    <sequence_number>1</sequence_number>
                    <Affiliation>
                        <organization_name>Goddard Space Flight Center</organization_name>
                        <organization_rorid>https://ror.org/0171mag52</organization_rorid>
                    </Affiliation>
                </Person>
            </List_Author>
        </Citation_Information>
        <Modification_History>
            <Modification_Detail>
                <modification_date>2025-02-18</modification_date>
                <version_id>1.0</version_id>
                <description>
                    This product, GGM0964A.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.                                                          
                </description>
            </Modification_Detail>
        </Modification_History>
    </Identification_Area>
    <Observation_Area>
        <Time_Coordinates>
            <start_date_time>1997-09-12T00:00:00Z</start_date_time>
            <stop_date_time>1999-03-27T23:59:59Z</stop_date_time>
        </Time_Coordinates>
        <Primary_Result_Summary>
            <purpose>Science</purpose>
            <processing_level>Derived</processing_level> 
            <description>Mars Global Surveyor Gravity Anomaly Maps Data</description>
        </Primary_Result_Summary> 
        <Investigation_Area>
            <name>Mars Global Surveyor</name>
            <type>Mission</type>
            <Internal_Reference>
                <lid_reference>urn:nasa:pds:context:investigation:mission.mars_global_surveyor</lid_reference> 
                <reference_type>data_to_investigation</reference_type>
            </Internal_Reference> 
        </Investigation_Area>
        <Observing_System>
            <Observing_System_Component>
                <name>Mars Global Surveyor</name>
                <type>Host</type> 
                <Internal_Reference>
                    <lid_reference>urn:nasa:pds:context:instrument_host:spacecraft.mgs</lid_reference> 
                    <reference_type>is_instrument_host</reference_type> 
                </Internal_Reference> 
            </Observing_System_Component> 
            <Observing_System_Component>
                <name>Radio Science Subsystem (RSS)</name>
                <type>Instrument</type> 
                <Internal_Reference>
                    <lid_reference>urn:nasa:pds:context:instrument:mgs.rss</lid_reference>
                    <reference_type>is_instrument</reference_type>
                </Internal_Reference> 
            </Observing_System_Component> 
        </Observing_System>  
        <Target_Identification> 
            <name>Mars</name> 
            <type>Planet</type>
            <Internal_Reference>
                <lid_reference>urn:nasa:pds:context:target:planet.mars</lid_reference> 
                <reference_type>data_to_target</reference_type> 
            </Internal_Reference> 
        </Target_Identification>
        <Discipline_Area>
            <cart:Cartography>
                <Local_Internal_Reference>
                    <local_identifier_reference>Array_3D_Image</local_identifier_reference>
                    <local_reference_type>cartography_parameters_to_image_object</local_reference_type>
                </Local_Internal_Reference>
                <cart:Spatial_Domain>
                    <cart:Bounding_Coordinates>
                        <cart:west_bounding_coordinate unit="deg">-179.5</cart:west_bounding_coordinate>
                        <cart:east_bounding_coordinate unit="deg">179.5</cart:east_bounding_coordinate>
                        <cart:north_bounding_coordinate unit="deg">89.5</cart:north_bounding_coordinate>
                        <cart:south_bounding_coordinate unit="deg">-89.5</cart:south_bounding_coordinate>
                    </cart:Bounding_Coordinates>
                </cart:Spatial_Domain>
                <cart:Spatial_Reference_Information>
                    <cart:Horizontal_Coordinate_System_Definition>
                        <cart:Planar>
                            <cart:Map_Projection>
                                <cart:map_projection_name>Equirectangular</cart:map_projection_name>
                                <cart:Equirectangular>
                                    <cart:latitude_of_projection_origin unit="deg">0</cart:latitude_of_projection_origin>
                                    <cart:standard_parallel_1 unit="deg">0</cart:standard_parallel_1>
                                    <cart:longitude_of_central_meridian unit="deg">0</cart:longitude_of_central_meridian>
                                </cart:Equirectangular>
                            </cart:Map_Projection>
                            <cart:Planar_Coordinate_Information>
                                <cart:planar_coordinate_encoding_method>Coordinate Pair</cart:planar_coordinate_encoding_method>
                                <cart:Coordinate_Representation>
                                    <cart:pixel_resolution_x unit="m/pixel">59110.0455857414781</cart:pixel_resolution_x>
                                    <cart:pixel_resolution_y unit="m/pixel">59274.6975233062185</cart:pixel_resolution_y>
                                    <cart:pixel_scale_x unit="pixel/deg">1.00278551532033422</cart:pixel_scale_x>
                                    <cart:pixel_scale_y unit="pixel/deg">1</cart:pixel_scale_y>
                                </cart:Coordinate_Representation>
                            </cart:Planar_Coordinate_Information>
                            <cart:Geo_Transformation>
                                <cart:upperleft_corner_x unit="m">-10669445.5541951191</cart:upperleft_corner_x>
                                <cart:upperleft_corner_y unit="m">5334722.77709755953</cart:upperleft_corner_y>
                            </cart:Geo_Transformation>
                        </cart:Planar>
                        <cart:Geodetic_Model>
                            <cart:latitude_type>Planetocentric</cart:latitude_type>
                            <cart:spheroid_name>MGM0964C18</cart:spheroid_name>
                            <cart:a_axis_radius unit="m">3396190</cart:a_axis_radius>
                            <cart:b_axis_radius unit="m">3396190</cart:b_axis_radius>
                            <cart:c_axis_radius unit="m">3396190</cart:c_axis_radius>
                            <cart:longitude_direction>Positive East</cart:longitude_direction>
                        </cart:Geodetic_Model>
                    </cart:Horizontal_Coordinate_System_Definition>
                </cart:Spatial_Reference_Information>
            </cart:Cartography>
            <disp:Display_Settings>
                <Local_Internal_Reference>
                    <local_identifier_reference>Array_3D_Image</local_identifier_reference>
                    <local_reference_type>display_settings_to_array</local_reference_type>
                </Local_Internal_Reference>
                <disp:Display_Direction>
                    <disp:horizontal_display_axis>Sample</disp:horizontal_display_axis>
                    <disp:horizontal_display_direction>Left to Right</disp:horizontal_display_direction>
                    <disp:vertical_display_axis>Line</disp:vertical_display_axis>
                    <disp:vertical_display_direction>Top to Bottom</disp:vertical_display_direction>
                </disp:Display_Direction>
            </disp:Display_Settings>
        </Discipline_Area>
    </Observation_Area>
    <Reference_List>
        <Internal_Reference>
            <lidvid_reference>urn:nasa:pds:mgs-rss:browse:ggm0964a::1.0</lidvid_reference>
            <reference_type>data_to_browse</reference_type>
        </Internal_Reference>
        <Internal_Reference>
            <lidvid_reference>urn:nasa:pds:mgs-rss:browse:ggm0964b::1.0</lidvid_reference>
            <reference_type>data_to_browse</reference_type>
        </Internal_Reference>
        <Internal_Reference>
            <lidvid_reference>urn:nasa:pds:mgs-rss:browse:ggm0964e::1.0</lidvid_reference>
            <reference_type>data_to_browse</reference_type>
        </Internal_Reference>
        <Internal_Reference>
            <lidvid_reference>urn:nasa:pds:mgs-rss:data-sha:ggm0964a::1.0</lidvid_reference>
            <reference_type>data_to_derived_product</reference_type>
        </Internal_Reference>
        <Source_Product_External> 
            <external_source_product_identifier>MGS-M-RSS-5-SDP-V1.0:anom.mgm0964c18.xyz:GGM0964A.IMG</external_source_product_identifier> 
            <reference_type>data_to_derived_source_product</reference_type>
            <doi>10.17189/1519757</doi> 
            <curating_facility>PDS Planetary Plasma Interactions Node</curating_facility> 
            <description> 
                This is the first version converted to PDS4. The DOI references the source PDS3 data set.  
            </description>
        </Source_Product_External>
    </Reference_List> 
    <File_Area_Observational>
        <File>
            <file_name>GGM0964A.IMG</file_name>
            <creation_date_time>1999-10-22T11:27:31</creation_date_time>
            <file_size unit="byte">129600</file_size>
            <md5_checksum>1d59bdd165d41890152693e80d33e626</md5_checksum>
        </File> 
        <Array_3D_Image>
            <local_identifier>Array_3D_Image</local_identifier>
            <offset unit="byte">0</offset>
            <axes>3</axes>
            <axis_index_order>Last Index Fastest</axis_index_order>
            <description>
                The model was constructed from 353,648 Mars Global Surveyor observations,    
                summarized in the table below.  MGS data are limited to tracking from the    
                Aerobraking Hiatus and Science Phasing Orbit (SPO) subphases of the          
                Orbit Insertion phase of the mission and to February and March 1999          
                after the orbit was circularized.  The solution used no data from either     
                Viking or Mariner 9.                                                         
                                                                                             
                            Time Periods                      Total                          
                       -----------------------            ------------                       
                       Hiatus and SPO                        257165                          
                       February and March 1999                96483                          
                       -----------------------            ------------                       
                       Total                                 353648                          
                                 
            </description>
            <Element_Array>
                <data_type>SignedMSB2</data_type>
                <unit>mm/s/s</unit>
            </Element_Array>
            <Axis_Array>
                <axis_name>Band</axis_name>
                <elements>1</elements>
                <sequence_number>1</sequence_number>
            </Axis_Array>
            <Axis_Array>
                <axis_name>Line</axis_name>
                <elements>180</elements>
                <sequence_number>2</sequence_number>
            </Axis_Array>
            <Axis_Array>
                <axis_name>Sample</axis_name>
                <elements>360</elements>
                <sequence_number>3</sequence_number>
            </Axis_Array>
            <Special_Constants>
                <missing_constant>-32768</missing_constant>
            </Special_Constants>
            <Object_Statistics>
                <description>
                    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. 
                </description>
            </Object_Statistics>
        </Array_3D_Image>
    </File_Area_Observational>
</Product_Observational>
