{"object":{"spkid":"20000511","des":"511","neo":false,"fullname":"511 Davida (A903 KB)","orbit_id":"128","orbit_class":{"code":"MBA","name":"Main-belt Asteroid"},"shortname":"511 Davida","pha":false,"prefix":null,"kind":"an"},"phys_par":[{"sigma":null,"ref":"MPO980529","title":"absolute magnitude","value":"6.42","notes":"IRAS observations used: 22","desc":"absolute magnitude (magnitude at 1 au from Sun and observer)","name":"H","units":null},{"title":"magnitude slope","sigma":null,"ref":"PDS3 (MPC 17259)","desc":"magnitude slope parameter used in the standard asteroid H/G magnitude law","units":null,"name":"G","value":"0.16","notes":"Fit"},{"title":"diameter","sigma":"1.045","ref":"urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)","desc":"effective body diameter","name":"diameter","units":"km","notes":null,"value":"270.327"},{"value":"5.1297","notes":"REFERENCE LIST:[Groeneveld, I.; Kuiper, G.P. (1954) Astrophys. J. 120, 200-220.], [Gehrels, T.; Owings, D. (1962) Astrophys. J. 135, 906-924.], [Chang, Y.C.; Chang, C.-S. (1963) Acta Astron. Sin. 11, 139-149.], [Di Martino, M.; Zappala, V.; De Campos, J.A.; Debehogne, H.; Lagerkvist, C.-I. (1987) Astron. Astrophys. Suppl. Ser. 67, 95-101.], [Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R.; Greenberg, R.; et al. (1987) Icarus 70, 191-245.], [Drummond, J.D.; Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R. (1988) Icarus 76, 19-77.], [Magnusson, P. (1990) Icarus 85, 229-240.], [Drummond, J.D.; Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R. (1991) Icarus 89, 44-64.], [Michalowski, T. (1993) Icarus 106, 563-572.], [De Angelis, G. (1995) Planet. Space Sci. 43, 649-682.], [Torppa, J.; Kaasalainen, M.; Michalowski, T.; Kwiatkowski, T.; et al. (2003) Icarus 164, 346-383.], [Behrend, R. (2005) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Marchis, F.; Kaasalainen, M.; Hom, E.F.Y.; Berthier, J.; et al. (2006) Icarus 185, 39-63.], [Alton, K.B. (2009) Minor Planet Bull. 36, 144-145.], [Behrend, R. (2010) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Garlitz, J. (2013) Posting on CALL web site. https://minplanobs.org/MPInfo/php/call.php], [Behrend, R. (2015) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Hanus, J.; Durech, J.; Oszkiewicz, D.A.; Behrend, R.; et al. (2016) Astron. Astrophys. 586, A108.], [Viikinkoski, M.; Hanus, J.; Kaasalainen, M.; Marchis, F.; Durech, J. (2017) Astron. Astrophys. 607, A117.], [Cellino, A.; Hestroffer, D.; Lu, X.-P.; Muinonen, K.; Tanga, P. (2019) Astron. Astrophys. 631, A67.], [Behrend, R. (2021) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Martikainen, J.; Muinonen, K.; Penttila, A.; Cellino, A.; Wang, X.-B. (2021) Astron. Astrophys. 649, A98.], [Vernazza, P.; Ferrais, M.; Jorda, L.; Hanus, J.; et al. (2021) Astron. Astrophys 654, id. A56.]","desc":"body rotation period (synodic)","name":"rot_per","units":"h","sigma":null,"ref":"LCDB (Rev. 2023-October); Warner et al., 2009","title":"rotation period"},{"desc":"geometric albedo","name":"albedo","units":null,"notes":null,"value":"0.076","title":"geometric albedo","ref":"urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)","sigma":"0.007"},{"name":"BV","units":null,"desc":"color index B-V magnitude difference","value":"0.717","notes":"#obs=23; phase (min.=1.78, mean=10.93, max.=20.90) deg.","title":"B-V","ref":"EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2","sigma":"0.013"},{"sigma":"0.020","ref":"EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2","title":"U-B","value":"0.363","notes":"#obs=11; phase (min.=1.53, mean=8.22, max.=17.13) deg.","desc":"color index U-B magnitude difference","units":null,"name":"UB"},{"value":"C","notes":"used 7 color indices; used ground-based radiometric albedo","desc":"Tholen spectral taxonomic classification","name":"spec_T","units":null,"ref":"EAR-A-5-DDR-TAXONOMY-V4.0","sigma":null,"title":"Tholen spectral type"},{"title":"SMASSII spectral type","sigma":null,"ref":"EAR-A-5-DDR-TAXONOMY-V4.0","desc":"SMASSII spectral taxonomic classification","units":null,"name":"spec_B","value":"C","notes":"based on a high-resolution spectrum by Xu et al. 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