CCSD3ZF0000100000001NJPL3IF0PDS200000001 = SFDU_LABEL /* File Format and Length */ RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 33 FILE_RECORDS = 5838 DATA_SET_ID = "A-5-DDR-ASTERMAG-V1.0" /* Record Pointer to Major Object */ ^TABLE = "ASTERMAG.TAB" /* Description of Object in File */ RECORD_FORMAT = "(I4,1X,F5.2,1X,F5.2,1X,A1,1X,A9,1X,A1)" OBJECT = TABLE ROWS = 5838 ROW_BYTES = 33 INTERCHANGE_FORMAT = ASCII COLUMNS = 6 DESCRIPTION = " Contents: IAU-adopted magnitude parameters (absolute V magnitude and slope parameter) for all numbered asteroids. Date: 1994 February 12 Comments: The absolute magnitude is variously given to 0.01, 0.1, or 1.0 mag precision, depending on the accuracy and consistency of the data used to arrive at the value. Those slope parameters that were determined by fitting the IAU-adopted phase function to data are given an origin code letter of 'f' (for 'fitted'); all others are given a code letter of 'a' (for 'assumed'). The default value is 0.15 in all cases. Note that because most absolute magnitudes are based on apparent magnitudes measured at non-zero phase angles, the value of the absolute magnitude does depend on the assumed value for the slope parameter. A change in the assumed value of the slope parameter (based on a taxonomic classification, for example) should not be made independently of the absolute magnitude. 'MPC' in the reference field stands for 'Minor Planet Circular', published on behalf of Commission 20 of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138. Updated mean absolute magnitudes H and slope parameters G were prepared by E. Tedesco, Jet Propulsion Laboratory, and published in MPC 17257 (Dec. 2, 1990). Details of the update are described in MPC 17257. This file contains magnitude parameters for all asteroids numbered as of the 1994 January 27 batch of Minor Planet Circulars and includes 5838 entries. Although errors are known to exist, more accurate values have yet to be adopted by the IAU. In two cases, described in the notes below, the IAU values were replaced by better ones. Improved values will be incorporated into this database after they become formally adopted. The Asteroid Subnode of the Planetary Data System would be happy to accept published values of improved magnitude parameters for forwarding to the appropriate IAU committee. References: Bowell, E., B. Hapke, D. Domingue, K. Lumme, J. Peltoniemi, and A. W. Harris 1989. Application of photometric models to asteroids. In Asteroids II (R. P. Binzel, T. Gehrels, and M. S. Matthews, Eds.), pp. 524-556. Univ. of Arizona Press, Tucson. Spencer, J. R., L. A. Akimov, C. Angeli, P. Angelini, M. A. Barrucci, P. Birch, C. Blanco, M. Buie, A. Caruso, V. G. Chiornij, F. Colas, P. Dentchev, M. C. DeSanctis, E. Dotto, M. Fulchignoni, S. Green, A. Harris, T. Hudecek, A. V. Kalashnikov, V. V. Kobelev, V. P. Kozhevnikov, Y. Krugly, D. Lazzaro, J. Lecacheux, J. MacConnell, T. Michalowski, R. A. Mohamed, B. Mueller, T. Nakamura, C. Neese, W. Osborn, P. Pravec, D. Riccioli, V. Shevchenko, D. Tholen, F. Velichko, C. Venditti, R. Venditti, W. Wisniewski, J. Young, B. Zellner 1994. The lightcurve of 4179 Toutatis: Evidence for complex rotation. Icarus (submitted). " OBJECT = COLUMN NAME = "ASTEROID_ID" DATA_TYPE = ASCII_INTEGER START_BYTE = 1 BYTES = 5 FORMAT = I5 END_OBJECT OBJECT = COLUMN NAME = "ABSOLUTE_V_MAGNITUDE" UNIT = "MAGNITUDE" DESCRIPTION = " The absolute magnitude is variously given to 0.01, 0.1, or 1.0 mag precision, depending on the accuracy and consistency of the data used to arrive at the value. " DATA_TYPE = ASCII_REAL START_BYTE = 7 BYTES = 5 FORMAT = "F5.2" END_OBJECT OBJECT = COLUMN NAME = "SLOPE_PARAMETER" DESCRIPTION = " Those slope parameters that were determined by fitting the IAU-adopted phase function to data are given an origin code letter of 'f' (for 'fitted'); all others are given a code letter of 'a' (for 'assumed'). The default value is 0.15 in all cases. Note that because most absolute magnitudes are based on apparent magnitudes measured at non-zero phase angles, the value of the absolute magnitude does depend on the assumed value for the slope parameter. A change in the assumed value of the slope parameter (based on a taxonomic classification, for example) should not be made independently of the absolute magnitude. " DATA_TYPE = ASCII_REAL START_BYTE = 13 BYTES = 5 FORMAT = "F5.2" END_OBJECT OBJECT = COLUMN NAME = "SLOPE_PARAMETER_ORIGIN_FLAG" DESCRIPTION = " Those slope parameters that were determined by fitting the IAU-adopted phase function to data are given an origin code letter of 'f' (for 'fitted'); all others are given a code letter of 'a' (for 'assumed'). " DATA_TYPE = CHARACTER START_BYTE = 19 BYTES = 1 FORMAT = A1 END_OBJECT OBJECT = COLUMN NAME = "REFERENCE" DESCRIPTION = " This file contains magnitude parameters for all asteroids numbered as of the 1994 January 27 batch of Minor Planet Circulars and includes 5838 entries. Although errors are known to exist, more accurate values have yet to be adopted by the IAU. In two cases, described in the notes column below, The IAU-adopted values were replaced by better ones. Improved values will be incorporated into this database after they become formally adopted. The Asteroid Subnode of the Planetary Data System would be happy to accept published values of improved magnitude parameters for forwarding to the appropriate IAU committee. " DATA_TYPE = CHARACTER START_BYTE = 21 BYTES = 9 FORMAT = A9 END_OBJECT OBJECT = COLUMN NAME = "NOTE" DESCRIPTION = "Comments on individual entries in this dataset: 1 - The absolute magnitude of 16 for 878 Mildred was adopted by the IAU prior to the recovery of this formerly lost asteroid (see MPC 17260). Following recovery, the inclusion of new and recent astrometric observations led to a significant revision of the absolute magnitude for this object (see MPC 18400). This dataset reflects this more recent value, rather than the older, IAU-adopted value. 2 - The IAU-adopted absolute magnitude of 14.0 for 4179 Toutatis (see MPC 17271) was known to be seriously in error prior to this Apollo asteroid's 1992 December 08 close approach to the Earth. The values included here are from Spencer et al. 1994. " DATA_TYPE = CHARACTER START_BYTE = 31 BYTES = 1 FORMAT = A1 END_OBJECT END_OBJECT END