PDS_VERSION_ID = "PDS3" RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 122 FILE_RECORDS = 6217 ^SHADR_HEADER_TABLE = ("JGMRO_110B2_SHA.TAB",1) ^SHADR_COEFFICIENTS_TABLE = ("JGMRO_110B2_SHA.TAB",3) INSTRUMENT_HOST_NAME = "MARS RECONNAISSANCE ORBITER" TARGET_NAME = "MARS" INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM" DATA_SET_ID = "MRO-M-RSS-5-SDP-V1.0" OBSERVATION_TYPE = "GRAVITY FIELD" ORIGINAL_PRODUCT_ID = "MRO110B2" PRODUCT_ID = "JGMRO_110B2_SHA.TAB" PRODUCT_RELEASE_DATE = 2009-08-13 DESCRIPTION = " This file contains coefficients and related data for the JPL Mars gravity field MRO110B2, a 110th degree and order spherical harmonic model. This field is identical to MRO110B except a 35% looser gravity constraint is applied beginning at degree 80 (compared to degree 70 for MRO110B). The data included in the solution is same as MRO110B. The summary of radio tracking data this gravity field is as follows: 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) including fixed high-gain antenna mapping 1999-02-02 to 1999-03-29 Mapping Orbit (MAP) 1999-03-29 to 2006-09-23 Note: This solution contains all useful MGS data prior to loss of contact with the spacecraft in Nov., 2006. Odyssey Transition Orbit (ODYT) 2002-01-11 to 2002-01-15 Mapping Orbit (ODYM) 2002-02-11 to 2008-10-28 MRO Transition Orbit (MROT) 2006-08-30 to 2006-09-11 Mapping Orbit (MROM) 2006-09-11 to 2008-10-31 Pathfinder 1997-07-04 to 1997-10-07 Viking 1 Lander 1976-07-21 to 1982-11-13 Some details describing this model are: The spherical harmonic coefficients are fully normalized. The reference radius = 3396.0 km The prime meridian of this model matches the IAU 2000 prime meridian at the J2000 epoch to about 20 cm. The Mars System GM (Mars+Phobs+Deimos) = 42828.3745268 km^3/sec^2 The GM of Mars = 42828.373716 km^3/sec^2 The GM of Phobos = 7.17x10^-4 km^3/sec^2 The GM of Deimos = 9.43x10^-5 km^3/sec^2 The Viking and Mariner 9 orbiter data are not included in this delivery unlike some past deliveries which included this data. This data do not seem to add any more information for the gravity although there is some Phobos and Deimos GM information in the data. The values for the Phobos and Deimos GM given here do not include the Viking and Mariner 9 orbiter data. The Mars-fixed reference frame is given by Konopliv et al. (2006) except with updated orientation parameters that are either estimated in the MRO110B2 solution or fixed to chosen values. The prime meridian of the MRO110B2 coordinate was chosen so that it matches the prime meridian of the IAU 2000 coordinate frame to about 20 cm. The rotation from the body-fixed position rBF to the inertial postion rIN is: rIN = Rz(-N) Rx(-J) Rz(-PSI) Rx(-I) Rz(-PHI) rBF where N is the angle in the plane of the Earth-mean-equator of J2000 (EME2000) from the vernal equinox (intersection of the mean ecliptic and EME2000 planes) to the intersection of the Mars-mean-orbit of J2000 and EME2000 planes; J is the inclination of the Mars-mean-orbit plane relative to the EME2000 plane; PSI is the angle in the Mars-mean-orbit plane from the intersection of the EME2000 and Mars-mean-orbit planes to the intersection of the Mars-mean-orbit and Mars-true-equator of date planes; I is the inclination of the Mars-true-equator relative to the Mars-mean-orbit plane; PHI is the angle in the plane of the Mars-true-equator from the intersection of the Mars-mean-orbit plane and Mars-true-equator to the Mars prime meridian. PSI, I, and PHI have J2000 epoch and secular values plus corrections for nuations. PHI in addition has seasonal corrections for spin. For example, PSI = PSI(t=J2000) + (dPSI/dt)*T + dPSI(nutations) where T is time past J2000 in days. For MRO110B2, the values of the orientation angles are: N = 3.37919183 deg (fixed) J = 24.67682669 deg (fixed) PSI(t=J2000) = 81.9683722766 deg (estimated) dPSI/dt = -0.0000057723 deg/day (estimated) I(t=J2000) = 25.1893792629 deg (estimated) dI/dt = -0.000000003 deg/day (estimated) PHI(t=J2000) = 133.38462 deg (fixed) dPHI/dt = 350.891985303 deg/day (estimated) The estimated seasonal spin amplitudes for PHI with periods equal to a Mars year, 1/2 year, 1/3 year, and 1/4 year and an epoch of Jan. 1999 are given by PHI( 1yr,cosine) = 435 milliarcseconds PHI( 1yr, sine) = -168 milliarcseconds PHI(1/2yr,cosine) = -97 milliarcseconds PHI(1/2yr, sine) = -119 milliarcseconds PHI(1/3yr,cosine) = -17 milliarcseconds PHI(1/3yr, sine) = -17 milliarcseconds PHI(1/4yr,cosine) = -9 milliarcseconds PHI(1/4yr, sine) = -4 milliarcseconds The number of radio tracking data (Doppler and range) observations for the various data blocks are as follows: MGS SPO1 and SPO2 at 177 km periapsis = 131,623 MGS GCO at 370 km periapsis = 140,735 MGS MAP at 370 km periapsis = 8,366,012 Odyssey transistion at 200 km periapsis = 27,661 Odyssey mapping at 390 km periapsis = 6,494,973 Pathfinder on the Mars surface = 7,562 Viking 1 Lander on the Mars surface = 15,628 MRO transition at 200 km periapsis = 72,127 MRO mapping at 250 km periapsis = 2,536,266 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. A kaula type power law constraint is applied to the spherical harmonics coefficients beginning at degree 80. The MRO110B2 constraint uses a similar taper as the constraint applied to MGS95J (see Fig. 5 of Konopliv et al., 2006), but begins at degree 80. The k2 Love number to use with this MRO110B2 solution is 0.183. The second degree harmonic coefficients do not include the permanent tide due to the Love number. This delivery is the Mars static gravity field. However, the gravity field varies due to the mass exchange between the polar caps and the Mars atmosphere. The major component of this effect can be included in the gravity field by adding the following correction to the normalized J3 gravity coefficient: dJ3 = 2.994D-09 * sin W*(t-t0) where W is the Mars mean motion = 191.39 deg/yr and t-t0 = years past Jan 1, 1999. This file is a pair of ASCII tables: a header table and a table of 9215 coefficients plus a value for GM. Definitions of the tables follow." START_TIME = 2006-08-30T18:00:00.000 STOP_TIME = 2008-10-31T16:00:00.000 PRODUCT_CREATION_TIME = 2009-01-12T00:00:00.000 PRODUCER_FULL_NAME = "ALEX S. KONOPLIV" PRODUCER_INSTITUTION_NAME = "JET PROPULSION LABORATORY" PRODUCT_VERSION_TYPE = "FINAL" PRODUCER_ID = "MRO GST" SOFTWARE_NAME = "SHAGRV.V1.0" OBJECT = SHADR_HEADER_TABLE ROWS = 1 COLUMNS = 8 ROW_BYTES = 137 ROW_SUFFIX_BYTES = 107 INTERCHANGE_FORMAT = ASCII DESCRIPTION = "The SHADR header includes descriptive information about the spherical harmonic coefficients which follow in SHADR_COEFFICIENTS_TABLE. The header consists of a single record of eight (delimited) data columns requiring 137 bytes, a pad of 105 unspecified ASCII characters, an ASCII carriage-return, and an ASCII line-feed." OBJECT = COLUMN NAME = "REFERENCE RADIUS" DATA_TYPE = ASCII_REAL START_BYTE = 1 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "The assumed reference radius of the spherical planet." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "CONSTANT" DATA_TYPE = ASCII_REAL START_BYTE = 25 BYTES = 23 FORMAT = "E23.16" UNIT = "N/A" DESCRIPTION = "For a gravity field model the assumed gravitational constant GM in kilometers cubed per seconds squared for the planet. For a topography model, set to 1." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "UNCERTAINTY IN CONSTANT" DATA_TYPE = ASCII_REAL START_BYTE = 49 BYTES = 23 FORMAT = "E23.16" UNIT = "N/A" DESCRIPTION = "For a gravity field model the uncertainty in the gravitational constant GM in kilometers cubed per seconds squared for the planet. For a topography model, set to 0." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "DEGREE OF FIELD" DATA_TYPE = ASCII_INTEGER START_BYTE = 73 BYTES = 5 FORMAT = "I5" UNIT = "N/A" DESCRIPTION = "The degree of model field." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ORDER OF FIELD" DATA_TYPE = ASCII_INTEGER START_BYTE = 79 BYTES = 5 FORMAT = "I5" UNIT = "N/A" DESCRIPTION = "The order of the model field." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "NORMALIZATION STATE" DATA_TYPE = ASCII_INTEGER START_BYTE = 85 BYTES = 5 FORMAT = "I5" UNIT = "N/A" DESCRIPTION = "The normalization indicator. For gravity field: 0 coefficients are unnormalized 1 coefficients are normalized 2 other." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "REFERENCE LONGITUDE" POSITIVE_LONGITUDE_DIRECTION = "EAST" DATA_TYPE = ASCII_REAL START_BYTE = 91 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "The reference longitude for the spherical harmonic expansion; normally 0." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "REFERENCE LATITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 115 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "The reference latitude for the spherical harmonic expansion; normally 0." END_OBJECT = COLUMN END_OBJECT = SHADR_HEADER_TABLE OBJECT = SHADR_COEFFICIENTS_TABLE ROWS = 6215 COLUMNS = 6 ROW_BYTES = 107 ROW_SUFFIX_BYTES = 15 INTERCHANGE_FORMAT = ASCII DESCRIPTION = "The SHADR coefficients table contains the coefficients for the spherical harmonic model. Each row in the table contains the degree index m, the order index n, the coefficients Cmn and Smn, and the uncertainties in Cmn and Smn. The (delimited) data require 107 ASCII characters; these are followed by a pad of 13 unspecified ASCII characters, an ASCII carriage- return, and an ASCII line-feed." OBJECT = COLUMN NAME = "COEFFICIENT DEGREE" DATA_TYPE = ASCII_INTEGER START_BYTE = 1 BYTES = 5 FORMAT = "I5" UNIT = "N/A" DESCRIPTION = "The degree index m of the C and S coefficients in this record." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "COEFFICIENT ORDER" DATA_TYPE = ASCII_INTEGER START_BYTE = 7 BYTES = 5 FORMAT = "I5" UNIT = "N/A" DESCRIPTION = "The order index n of the C and S coefficients in this record." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "C" DATA_TYPE = ASCII_REAL START_BYTE = 13 BYTES = 23 FORMAT = "E23.16" UNIT = "N/A" DESCRIPTION = "The coefficient Cmn for this spherical harmonic model." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "S" DATA_TYPE = ASCII_REAL START_BYTE = 37 BYTES = 23 FORMAT = "E23.16" UNIT = "N/A" DESCRIPTION = "The coefficient Smn for this spherical harmonic model." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "C UNCERTAINTY" DATA_TYPE = ASCII_REAL START_BYTE = 61 BYTES = 23 FORMAT = "E23.16" UNIT = "N/A" DESCRIPTION = "The uncertainty in the coefficient Cmn for this spherical harmonic model." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "S UNCERTAINTY" DATA_TYPE = ASCII_REAL START_BYTE = 85 BYTES = 23 FORMAT = "E23.16" UNIT = "N/A" DESCRIPTION = "The uncertainty in the coefficient Smn for this spherical harmonic model." END_OBJECT = COLUMN END_OBJECT = SHADR_COEFFICIENTS_TABLE END