urn:nasa:pds:mess_rs_derived:data:jgmess_160a_sha 1.0 1.11.0.0 Product_Observational 2019-07-30 1.0 First release of this product 2011-03-18T06:00:00.000Z 2015-04-30T00:02:00.000Z MESSENGER Mission urn:nasa:pds:context:investigation:mission.messenger data_to_investigation MESSENGER Spacecraft urn:nasa:pds:context:instrument_host:spacecraft.mess is_instrument_host Radio Science Subsystem Instrument urn:nasa:pds:context:instrument:rss.mess is_instrument Mercury Planet urn:nasa:pds:context:target:planet.mercury data_to_target SHADR SHAGRV.V1.0 10.1016/j.icarus.2019.07.020 Konopliv, A.S., R.S. Park, and A.I. Ermakov, The Mercury gravity field, orientation, Love number, and ephemeris from the MESSENGER radiometric tracking data, Icarus, doi:10.1016/j.icarus.2019.07.020, 2019. jgmess_160a_sha.tab 2019-07-30 This file contains coefficients and related data for the JPL Mercury gravity field MESS160A, a 160th degree and order spherical harmonic model. It is the first archived JPL gravity field that includes MESSENGER tracking data. Some details describing this model are: The spherical harmonic coefficients are fully normalized. The reference radius = 2440.0 km The Mercury-fixed reference frame is given by the IAU right ascension (RA) and declination (DEC) coordinate system with the following values for the angles and rate. Parameters estimated together with the gravity field are noted as well as those held fixed. RA = 281.0138 +/- 0.0025 deg (estimated) dRA/dt = -0.0328 deg/cty (fixed) DEC = 61.4161 +/- 0.0017 deg (estimated) dDEC/dt = -0.0049 deg/cty (fixed) W0 = 329.75 deg (fixed) dW/dt = 6.138514 +/- 0.000006 deg/day (estimated) A kaula power law constraint is applied to the spherical harmonics coefficients for all harmonic degrees as 5x10^-5 /n^2. The k2 Love number to use with this MESS160A solution is 0.53. The second degree harmonic coefficients do not include the permanent tide due to the Love number. This reference for this gravity field is Konopliv et al., The Mercury gravity field, orientation, Love number, and ephemeris from the MESSENGER radiometric tracking data, Icarus 335, 253-260, 2020, https://doi.org/10.1016/j.icarus.2019.07.020. This file is a pair of ASCII tables: a header table and a table of 14640 coefficients plus a value for GM. Definitions of the tables follow. SHADR Header Table 0 1 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. Carriage-Return Line-Feed 8 0 244 reference radius 1 1 ASCII_Real 23 km 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 kilometers 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 kilometers cubed per seconds squared for the planet. For a topography model, set to 0. degree of field 4 73 ASCII_Integer 5 The degree of the model field. order of field 5 79 ASCII_Integer 5 The 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 degree The reference longitude for the spherical harmonic expansion; normally 0. reference latitude 8 115 ASCII_Real 23 degree The reference latitude for the spherical harmonic expansion; normally 0. SHADR Coefficients Table 244 13040 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. Carriage-Return Line-Feed 6 0 122 coefficient degree 1 1 ASCII_Integer 5 The degree index m of the C and S coefficients in this record. coefficient order 2 7 ASCII_Integer 5 The order index n of the C and S coefficients in this record. c 3 13 ASCII_Real 23 The coefficient Cmn for this spherical harmonic model. s 4 37 ASCII_Real 23 The coefficient Smn for this spherical harmonic model. c uncertainty 5 61 ASCII_Real 23 The uncertainty in the coefficient Cmn for this spherical harmonic model. s uncertainty 6 85 ASCII_Real 23 The uncertainty in the coefficient Smn for this spherical harmonic model. jgmess_160a_sha.lbl 0 PDS3 Original PDS3 label Carriage-Return Line-Feed