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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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      http://pds.nasa.gov/pds4/pds/v1
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      http://pds.nasa.gov/pds4/cart/v1
      https://pds.nasa.gov/pds4/cart/v1/PDS4_CART_1M00_1970.xsd

      http://pds.nasa.gov/pds4/disp/v1
      https://pds.nasa.gov/pds4/disp/v1/PDS4_DISP_1M00_1510.xsd

      http://pds.nasa.gov/pds4/geom/v1
      https://pds.nasa.gov/pds4/geom/v1/PDS4_GEOM_1M00_1970.xsd
     ">
    <Identification_Area>
        <logical_identifier>urn:nasa:pds:mgs-rss:data-maps:gom1041c</logical_identifier> 
        <version_id>1.0</version_id>
        <title>MGS Digital Map of the Mars Geoid for the MGM1041C Model to 72x72</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 geoid evaluated for 
                the MGM1041C model to 72x72 from the Mars Global Surveyor. These 
                data cover 1997-10-13T00:00:00Z to 2002-05-27T23:59:59Z.
            </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, GOM1041C.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>1997-10-13T00:00:00Z</start_date_time>
            <stop_date_time>2002-05-27T23:59:59Z</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">-180.0</cart:west_bounding_coordinate>
                        <cart:east_bounding_coordinate unit="deg">179.0</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>MGM1041C</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:data-sha:ggm1041c::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:geoid.mgm1041c.xyz.72:GOM1041C.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>GOM1041C.IMG</file_name>
            <creation_date_time>2003-11-25T16:38:34</creation_date_time>
            <file_size unit="byte">129600</file_size>
            <md5_checksum>c46a03cfcfaf4627c79a67a6afd5ebb8</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 2,568,683 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 from February 1999 to               
                    March 2002 after the orbit was circularized.                                 
                                                                                                 
                               Time Periods                      Total                           
                                                             Arcs  Observations                  
                          -----------------------            ----  ------------                  
                          Hiatus                               2       24119                     
                          SPO-1                                8       31014                     
                          SPO-2                               17      144253                     
                          Feb-Mar 1999                        10       86069                     
                          2 Apr 1999 - 22 May 2002           167     2186533                     
                          Doppler + Crossovers                 5       96875                     
                          -----------------------            ----  ------------                  
                          Total                                      2568863             
                </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 gives Mars geoid            
   height in meters.  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>
