PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2011-09-01 NOTE = "Description of contents of DATA directory" END_OBJECT = TEXT END The 3 data files in the DATA directory are described below. SHADR/GGLP_GLGM3150_SHA.TAB --------------------------- This file contains spherical harmonic coefficients and ancillary information for the GLGM-3 gravity model for the Moon and is complete to 150x150. The input data are the tracking data to the NASA Moon Orbiters including Lunar Orbiters 1-5 (1966-1968), the Apollo 15 and Apollo 16 subsatellites (1971-1972), Clementine (1994) and Lunar Prospector (1998-1999). This model is based on reanalysis completed in advance of the Lunar Reconnaissance Orbiter to the Moon. Due to the quantity of Lunar Prospector (LP) data, the model is in effect tuned to the LP orbit. The tracking data that were used consist of S Band Doppler tracking to these spacecraft from the antennae of the Deep Space Network (DSN). The Apollo 15 and 16 subsatellites were tracked by an independent tracking network (the MSFN, or Manned Space Flight Network). In addition, Clementine received a small amount of tracking from the Pomonkey S Band antenna operated by the Naval Research Lab in Southern Maryland. The tracking data were analyzed with the NASA GSFC Orbit Determination and Geodetic Parameter Estimation Program (GEODYN). The citation for this model is: Mazarico, E., F. G. Lemoine, S.-C. Han, and D. E. Smith (2010), GLGM-3: A degree-150 lunar gravity model from the historical tracking data of NASA Moon orbiters, J. Geophys. Res., 115, E05001, doi:10.1029/2009JE003472. (URL: http://www.agu.org/journals/je/je1005/2009JE003472/) The coordinate system for this model is the principal axis system as defined by the DE421 set of planetary ephemerides. Williams, J. G., D. H. Boggs, and W. M. Folkner (2008), DE421 lunar orbit, physical librations, and surface coordinates, Rep. IOM 335-JW,DB,WF-20080314-001, Jet Propul. Lab., Pasadena, Calif. The gravitational constant and the K2 Love number for the Moon were not adjusted, but held at a priori values from previous solutions. GM = 0.49028002380000D+13 m**3/sec**2 Reference Radius: 1738000.0 meters K2 = 0.027. The tracking data incorporated in this model are listed below: Mission Start End No. Arcs. No. Obs. Periapsis Apoapsis ------- ----- --- --------- -------- --------- -------- LO-1 08/10/66 10/27/66 70 48575 50 1830 LO-2 11/10/66 07/24/67 90 77726 50 1870 LO-3 02/09/67 10/06/67 73 62264 50 1820/320 LO-4 05/08/67 07/10/67 32 48688 2700/75 6000/4000 LO-5 08/05/67 01/29/68 70 42916 100/170 1750/2000 A15ss 08/29/71 05/19/72 93 52500 75 160 A16ss 04/27/72 05/29/72 46 42579 30 190 Clementine 02/19/94 05/04/94 40 378022 370 2960 LP nominal 01/11/98 12/18/98 184 2198751 90 45 LP extend 12/19/98 07/30/99 127 1372150 25 45 The average RMS of Fit (cm/s) and the Final Effective Data Weight for these data in GLGM-3 are listed below: Data RMS of fit Final Eff. Data Weight (cm/s) (cm/s) LO-1 0.24 3.16 LO-2 0.11 3.16 LO-3 0.07 3.16 LO-4 0.05 0.55 LO-5 0.21 0.49 A15ss 0.12 0.95 A16ss 0.15 0.32 Clementine 0.31 1.34 LP nominal 0.02 1.41 LP extended 0.25 3.78 This lunar gravity model was produced by Erwan Mazarico and Frank Lemoine under the auspices of the Lunar Reconnaissance Orbiter Project/ Lunar Orbiter Laser Altimeter (LOLA) Science Team. SHADR/GGLP_LPE200_SHA.TAB ------------------------- This file contains spherical harmonic coefficients and ancillary information for the LPE200 gravity model for the Moon and is complete to 200x200. The input data are the tracking data to the NASA Lunar Prospector (1998-1999), but only the data during the extended mission (the last 7 months). The tracking data that were used consist of S Band Doppler tracking to the LP spacecraft from the antennae of the Deep Space Network (DSN). The tracking data were analyzed with the NASA GSFC Orbit Determination and Geodetic Parameter Estimation Program (GEODYN). The citation for this model is: Han, S.-C., E. Mazarico, D. D. Rowlands, F. G. Lemoine, S. Goossens (2011), New analysis of Lunar Prospector radio tracking data brings the nearside gravity field of the Moon with an unprecedented resolution, Geophys. Res. Lett., submitted. This model is an update to GLGM-3 by analyzing the line-of-sight (LOS) acceleration residuals over the extended nearside (a spherical cap centered on 0N and 0E with a half angle of 100 degree). When evaluated over the areas beyond the extended nearside, LPE200 gives the same gravity anomaly as the a priori field, i.e., GLGM-3 (truncated to 120). The signal-to-noise ratio for low degree coefficients (for example, l,m < 20) is low partly due to the adjustment only for the extended nearside. See Han et al. [2011] for detail. The formal error gives the accuracy of the gravity field solution valid over the extended nearside. The gravitational constant and the K2 Love number for the Moon were not adjusted, but held at a priori values from previous solutions. GM = 0.49028002380000D+13 m**3/sec**2 Reference Radius: 1738000.0 meters K2 = 0.027. The tracking data incorporated in this model are listed below: Mission Start End No. Arcs. No. Obs. Periapsis Apoapsis ------- ----- --- --------- -------- --------- -------- LP extend 12/19/98 07/30/99 127 1372150 25 km 45 km SHBDR/GGLP_GLGM3_SHB.DAT ------------------------ This file contains coefficients and related data for a spherical harmonic model of the Lunar gravity field. Input data are from radio tracking of the Lunar Prospector spacecraft. This product is a set of binary tables: a header table, a names table, a coefficients table, and a covariance table. Definitions of the tables follow. This LP Lunar gravity model is in the form of a Spherical Harmonics Binary Data Record (SHBDR). It has been produced by the LRO Precision Orbit Determination Team at NASA GSFC. NOTE: The data is in little endian format. The COVARIANCE data is a row ordered (stored) upper triangular matrix.