{"object":{"des":"334","neo":false,"shortname":"334 Chicago","pha":false,"spkid":"20000334","prefix":null,"orbit_id":"199","orbit_class":{"name":"Outer Main-belt Asteroid","code":"OMB"},"fullname":"334 Chicago (A892 QB)","kind":"an"},"signature":{"version":"1.3","source":"NASA/JPL Small-Body Database (SBDB) API"},"phys_par":[{"title":"absolute magnitude","ref":"E2026-EA1","value":"7.63","units":null,"sigma":null,"notes":null,"name":"H","desc":"absolute magnitude (magnitude at 1 au from Sun and observer)"},{"name":"diameter","notes":null,"sigma":"5.597","desc":"effective body diameter","ref":"urn:nasa:pds:neowise_diameters_albedos::2.0[hildas] (http://adsabs.harvard.edu/abs/2012ApJ...744..197G)","title":"diameter","value":"198.770","units":"km"},{"value":"7.361","title":"rotation period","ref":"LCDB (Rev. 2023-October); Warner et al., 2009","units":"h","name":"rot_per","sigma":null,"notes":"REFERENCE LIST:[Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R.; Greenberg, R.; et al. (1990) Icarus 86, 402-447.], [Behrend, R. (2001) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Behrend, R. (2003) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Behrend, R. (2004) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Behrend, R. (2006) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Jutzeler, E.C.; Hausel, E.; Leake, M.; Burke, A. (2007) J. SE Assoc. for Research in Astron. 1, 2-6.], [Strabla, L.; Quadri, U.; Girelli, R. (2011) Minor Planet Bull. 38, 169-172.], [Slyusarev, I.G.; Shevchenko, V.G.; Belskaya, I.N.; Krugly, Yu.N.; Chiorny, V.G. (2012) ACM 2012, #6398.], [Behrend, R. (2019) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html], [Durech, J.; Hanus, J.; Vanco, R. (2019) Astron. Astrophys 631, A2.]","desc":"body rotation period (synodic)"},{"value":"0.041","title":"geometric albedo","ref":"urn:nasa:pds:neowise_diameters_albedos::2.0[hildas] (http://adsabs.harvard.edu/abs/2012ApJ...744..197G)","units":null,"sigma":"0.007","notes":null,"name":"albedo","desc":"geometric albedo"},{"desc":"color index B-V magnitude difference","notes":"#obs=5; phase (min.=5.04, mean=9.38, max.=14.21) deg.","sigma":"0.026","name":"BV","units":null,"title":"B-V","ref":"EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2","value":"0.736"},{"units":null,"value":"0.358","title":"U-B","ref":"EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2","desc":"color index U-B magnitude difference","name":"UB","notes":"#obs=6; phase (min.=5.04, mean=9.48, max.=14.21) deg.","sigma":"0.028"},{"desc":"Tholen spectral taxonomic classification","notes":"used 7 color indices","sigma":null,"name":"spec_T","units":null,"value":"C","ref":"EAR-A-5-DDR-TAXONOMY-V4.0","title":"Tholen spectral type"}],"orbit":{"producer":"Otto Matic","source":"JPL","first_obs":"1892-08-24","n_obs_used":6726,"two_body":null,"orbit_id":"199","moid":"2.82","pe_used":"DE441","model_pars":[],"sb_used":"SB441-N16","rms":"0.34","cov_epoch":"2457634.5","last_obs":"2026-04-07","not_valid_after":null,"elements":[{"units":null,"label":"e","title":"eccentricity","name":"e","value":"0.0284","sigma":"2.8e-09"},{"units":"au","label":"a","title":"semi-major axis","value":"3.94","name":"a","sigma":"1e-08"},{"sigma":"1.9e-08","title":"perihelion distance","value":"3.83","name":"q","label":"q","units":"au"},{"label":"i","units":"deg","sigma":"1.5e-07","title":"inclination; angle with respect to x-y ecliptic plane","name":"i","value":"4.72"},{"label":"node","units":"deg","sigma":"1.3e-06","title":"longitude of the ascending node","name":"om","value":"129"},{"label":"peri","units":"deg","sigma":"6.2e-06","title":"argument of perihelion","name":"w","value":"197"},{"title":"mean anomaly","name":"ma","value":"162","sigma":"7.5e-06","units":"deg","label":"M"},{"title":"time of perihelion passage","value":"2459913.267","name":"tp","sigma":"5.5e-05","units":"TDB","label":"tp"},{"label":"period","units":"d","sigma":"1.1e-05","title":"sidereal orbital period","value":"2860","name":"per"},{"label":"n","units":"deg/d","sigma":"5e-10","name":"n","value":"0.126","title":"mean motion"},{"label":"Q","units":"au","sigma":"1.1e-08","name":"ad","value":"4.05","title":"aphelion distance"}],"n_del_obs_used":null,"condition_code":"0","soln_date":"2026-06-05 03:28:20","moid_jup":"1.11","comment":null,"not_valid_before":null,"t_jup":"3.054","equinox":"J2000","epoch":"2461200.5","data_arc":"48803","n_dop_obs_used":null}}