urn:nasa:pds:mgs-rss:data-sha:jgm95i01 1.0 1.22.0.0 Product_Observational 2025 MGS RSS This file contains coefficients and related data for the spherical harmonic model MGS95I of the Mars gravity field. MGS95I is a 95x95 spherical harmonics model with power rule constraints applied to harmonics above degree 59. It was derived from radio tracking of the Mars Global Surveyor, Odyssey, Pathfinder and Viking 1 Lander spacecrafts. The data cover 1998-03-28T00:00:00.000Z to 2003-11-09T14:00:00.000Z. William Sjogren 1 Jet Propulsion Laboratory https://ror.org/027k65916 2025-02-26 1.0 This product, JGM95I01.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 2003-11-09T14:00:00.000Z 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 2001 Mars Odyssey Host urn:nasa:pds:context:instrument_host:spacecraft.ody is_instrument_host Mars Pathfinder Lander Host urn:nasa:pds:context:instrument_host:spacecraft.mpfl is_instrument_host Viking Lander 1 Host urn:nasa:pds:context:instrument_host:spacecraft.vl1 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:ody.rss is_instrument Radio Science Subsystem (RSS) Instrument urn:nasa:pds:context:instrument:rss.mpfl is_instrument Radio Science Subsystem (RSS) Instrument urn:nasa:pds:context:instrument:rss.vo1 is_instrument Mars Planet urn:nasa:pds:context:target:planet.mars data_to_target 202 20879 MGS-M-RSS-5-SDP-V1.0:JGM95I01.SHA:JGM95I01.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. JGM95I01.SHA 2004-02-17T14:45:22 568154 60b48427c81540d2f4a96709263a5d55 MGS Spherical Harmonic ASCII MGS95I Model Header 1998-03-28 - 2003-11-09 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 MGS95I Model Coefficients Table 1998-03-28 - 2003-11-09 244 567910 PDS DSV 1 The Mars System GM (Mars+Phobs+Deimos) = 42828.3752823 km^3/sec^2 The GM of Mars = 42828.374568 km^3/sec^2 The GM of Phobos = 7.14x10^-4 km^3/sec^2 The GM of Deimos = 8.2x10^-5 km^3/sec^2 Derived Radio Tracking of the MGS, Odyssey, Pathfinder and Viking Lander: 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 Fixed High-Gain Antenna Mapping (FHGA) 1999-02-02 to 1999-03-29 Mapping (MAP) 1999-03-29 to 2002-11-09 Odyssey Transition Orbit (ODYT) 2002-01-11 to 2002-01-15 Pathfinder 2002-02-11 to 1997-10-27 Viking 1 Lander 1976-07-21 to 1982-11-13 The radio tracking data (Doppler and range) blocks consist of: MGS SPO1 and SPO2 at 177 km periapsis with 133,624 observations; MGS GCO at 370 km periapsis with 144,810 observations; MGS MAP at 370 km periapsis with 4,613,848 observations. Odyssey transistion at 200 km periapsis with 27,661 observations. Pathfinder on the Mars surface with 7,562 observations. Viking 1 Lander on the Mars surface with 15,628 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 and MAP data are the highest quality data having a 2-way Doppler data weight near 0.03 mm/sec for a 10 second sample. The Pathfinder Doppler is weighted about 0.08 mm/s and Viking Lander data is weighted near 0.4 mm/s. 4655 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.