{"signature":{"version":"1.3","source":"NASA/JPL Small-Body Database (SBDB) API"},"object":{"fullname":"54 Alexandra (A858 RA)","pha":false,"prefix":null,"orbit_class":{"name":"Main-belt Asteroid","code":"MBA"},"spkid":"20000054","kind":"an","neo":false,"des":"54","orbit_id":"212","shortname":"54 Alexandra"},"phys_par":[{"notes":"IRAS observations used: 14","value":"7.94","title":"absolute magnitude","ref":"MPO980521","units":null,"sigma":null,"name":"H","desc":"absolute magnitude (magnitude at 1 au from Sun and observer)"},{"name":"diameter","desc":"effective body diameter","title":"diameter","ref":"urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)","sigma":"1.857","units":"km","notes":null,"value":"160.120"},{"value":"7.024","notes":"REFERENCE LIST:[Van Houten-Groeneveld, I.; van Houten, C.J.; Zappala, V. (1979) Astron. Astrophys. Suppl. Ser. 35, 223-232.], [Di Martino, M.; Zappala, V.; De Sanctis, G.; Cacciatori, S. (1987) Icarus 69, 338-353.], [Bel'skaya, I.N.; Dovgopol, A.N.; Erikson, A.; Lagerkvist, C.-I.; Oja, T. (1993) Astron. Astrophys. Suppl. Ser. 101, 507-511.], [Behrend, R. (2005) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Torppa, J.; Hentunen, V.-P.; Paakkonen, P.; Kehusmaa, P.; Muinonen, K. (2008) Icarus 198, 91-107.], [Warner, B.D.; Durech, J.; Faurerbach, M.; Marks, S. (2008) Minor Planet Bull. 35, 167-171.], [Higgins, D.; Warner, B.D. (2009) Minor Planet Bull. 36, 159-160.], [Durech, J.; Kaasalainen, M.; Herald, D.; Dunham, D.; et al. (2011) Icarus 214, 652-670.], [Durech, J. (2011) Database of Asteroid Models from Inversion Techniques (DAMIT). http://astro.troja.mff.cuni.cz/projects/asteroids3D/web.php], [Hanus, J.; Marchis, F.; Durech, J. (2013) Icarus 226, 1045-1057.], [Hanus, J.; Durech, J.; Oszkiewicz, D.A.; Behrend, R.; et al. (2016) Astron. Astrophys. 586, A108.], [Hanus, J.; Viikinkoski, M.; Marchis, F.; Durech, J.; et al (2017) Astron. Astrophys. 601, A114.], [Behrend, R. (2019) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Farfan, R.G.; de la Cuesta, F.G.; Casal, J.D.; Reina Lorenz, E.; et al. (2022) Minor Planet Bull. 49, 229-233.]","units":"h","sigma":null,"ref":"LCDB (Rev. 2023-October); Warner et al., 2009","title":"rotation period","desc":"body rotation period (synodic)","name":"rot_per"},{"notes":null,"value":"0.059","title":"geometric albedo","ref":"urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)","units":null,"sigma":"0.014","name":"albedo","desc":"geometric albedo"},{"value":"0.727","notes":"#obs=9; phase (min.=4.77, mean=11.55, max.=25.49) deg.","sigma":"0.027","units":null,"title":"B-V","ref":"EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2","desc":"color index B-V magnitude difference","name":"BV"},{"value":"0.357","notes":"#obs=7; phase (min.=4.77, mean=11.92, max.=25.49) deg.","units":null,"sigma":"0.037","ref":"EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2","title":"U-B","desc":"color index U-B magnitude difference","name":"UB"},{"notes":"used 7 color indices; used ground-based radiometric albedo","value":"C","ref":"EAR-A-5-DDR-TAXONOMY-V4.0","title":"Tholen spectral type","units":null,"sigma":null,"name":"spec_T","desc":"Tholen spectral taxonomic classification"},{"notes":"based on a high-resolution spectrum by Xu et al. 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