urn:nasa:pds:mgs-rss:data-sha:jgm85f01 1.0 1.22.0.0 Product_Observational 2025 MGS RSS This file contains coefficients and related data for the spherical harmonic model MGS85F of the Mars gravity field. MGS85F is a 85x85 spherical harmonics model with power rule constraints applied to harmonics above degree 59. It was derived from radio tracking of the Mariner 9, Viking 1 Orbiter, Viking 2 Orbiter, and Mars Global Surveyor spacecrafts. The Mars-fixed reference frame is given by the IAU 1991 constants. The data cover 1998-03-28T00:00:00.000Z to 2001-08-14T14:00:00.000Z. William Sjogren 1 Jet Propulsion Laboratory https://ror.org/027k65916 2025-02-25 1.0 This product, JGM85F01.SHA, 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 data themselves are unchanged. 1998-03-28T00:00:00.000Z 2001-08-14T14:00:00.000Z Science Derived Mars Global Surveyor Spherical Harmonic Model ASCII Data Mars Global Surveyor Mission urn:nasa:pds:context:investigation:mission.mars_global_surveyor data_to_investigation Mars Global Surveyor Host urn:nasa:pds:context:instrument_host:spacecraft.mgs is_instrument_host 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:mgs.rss is_instrument 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 202 10884 urn:nasa:pds:mgs-rss:data-maps:jgd85f60::1.0 data_to_derived_product urn:nasa:pds:mgs-rss:data-maps:jod85f60::1.0 data_to_derived_product MGS-M-RSS-5-SDP-V1.0:JGM85F01.SHA:JGM85F01.SHA 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. JGM85F01.SHA 2002-03-19T08:47:46 456524 433a19e4f7c9bbf6114426b59e6a528a MGS Spherical Harmonic ASCII MGS85F Model Header 1998-03-28 - 2001-08-14 0 1 Carriage-Return Line-Feed 8 0 244 Reference Radius 1 1 ASCII_Real 23 The assumed reference radius of the spherical planet. Constant 2 25 ASCII_Real 23 For a gravity field model the assumed gravitational constant GM in km cubed per seconds squared for the planet. For a topography model, set to 1. Uncertainty in Constant 3 49 ASCII_Real 23 For a gravity field model the uncertainty in the gravitational constant GM in km cubed per seconds squared for the planet (or, set to 0 if not known). For a topography model, set to 0. Degree of Field 4 73 ASCII_Integer 5 deg of the model field. Order of Field 5 79 ASCII_Integer 5 Order of the model field. Normalization State 6 85 ASCII_Integer 5 The normalization indicator. For gravity field: 0 coefficients are unnormalized 1 coefficients are normalized 2 other. Reference Longitude 7 91 ASCII_Real 23 deg The reference longitude for the spherical harmonic expansion; normally 0. Reference Latitude 8 115 ASCII_Real 23 deg The reference latitude for the spherical harmonic expansion; normally 0. MGS Spherical Harmonic ASCII MGS85F Model Coefficients Table 1998-03-28 - 2001-08-14 244 456280 PDS DSV 1 Derived Radio Tracking of the Mariner -9, Viking and Mars Global Surveyor spacecrafts: Mariner 9 1971-11-14 to 1972-04-14 Viking Orbiter 1 1976-06-21 to 1978-11-18 Viking Orbiter 2 1977-03-02 to 1978-07-25 MGS Science Phasing Orbit 1 (SPO1) 1998-03-28 to 1998-04-28 Science Phasing Orbit 2 (SPO2) 1998-06-04 to 1998-09-23 Gravity Calibration Orbit (GCO) and 1999-02-02 to 1999-03-29 Fixed High-Gain Antenna Mapping (FHGA) Mapping (MAP) 1999-03-29 to 2000-09-29 The radio tracking data blocks consist of: Mariner 9 with 47,597 observations; Viking Orbiter 1 with 67,545 observations; Viking Orbiter 2 with 70,677 observations; SPO1 and SPO2 at 177 km periapsis with 134,072 observations; GCO at 370 km periapsis with 145,777 observations. MAP at 370 km periapsis with 2,102,977 observations. The data weights for each block have accounted for the SPO1 and SPO2 Doppler being corrupted by solar plasma while at small sun-earth-probe angles. The GCO/FHGA and MAP data are the highest quality data having a 2-way Doppler data weight of 0.1 mm/sec for a 10 second sample. 3740 Carriage-Return Line-Feed Comma 6 0 Coefficient Degree 1 ASCII_Integer 5 %5d The degree index m of the C and S coefficients in this record. Coefficient Order 2 ASCII_Integer 5 %5d The order index n of the C and S coefficients in this record. C 3 ASCII_Real 23 %23.16e The coefficient Cmn for this spherical harmonic model. S 4 ASCII_Real 23 %23.16e The coefficient Smn for this spherical harmonic model. C Uncertainty 5 ASCII_Real 23 %23.16e The uncertainty in the coefficient Cmn for this spherical harmonic model. S Uncertainty 6 ASCII_Real 23 %23.16e The uncertainty in the coefficient Smn for this spherical harmonic model.