+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   31 Euphrosyne Classification: Main-belt Asteroid          SPK-ID: 2000031 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: JPL 62 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2222905343344933 3.5649e-08   a 3.153370865178287 7.6546e-09 AU q 2.452406370602982 1.131e-07 AU i 26.31663346538304 5.2534e-06 deg node 31.15239369935353 8.9238e-06 deg peri 61.28732746410908 1.5316e-05 deg M 60.49124609489693 1.2103e-05 deg tp 2456056.822553349601 (2012-May-09.32255335) 6.7886e-05 JED period 2045.318765628489 5.60 7.4473e-06 2.039e-08 d yr n .17601168387529 6.4089e-10 deg/d Q 3.854335359753592 9.3562e-09 AU   Orbit Determination Parameters    # obs. used (total)      1267      data-arc span      55696 days (152.49 yr)      first obs. used      1860-10-25      last obs. used      2013-04-22      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .63548      data source      ORB      producer      Otto Matic      solution date      2013-Apr-29 12:31:36   Additional Information  Earth MOID = 1.56307 AU   T_jup = 3.011  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 6.74 mag n/a IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19 diameter diameter 255.90 km 11.5 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19 rotation period rot_per 5.530 h n/a Asteroid Lightcurve DataBase (Rev. 2013-May-01) Published Reference List: [Schober, H.J.; Scaltriti, F.; Zappala, V.; Harris, A.W. (1980) Astron. Astrophys. 91, 1-6.] [Barucci, M.A.; Fulchignoni, M.; Burchi, R.; D'Ambrosio, V. (1985) Icarus 61, 152-162.] [Michalowski, T. (1993) Icarus 106, 563-572.] [Kryszczynska, A.; Colas, F.; Berthier, J.; Michalowski, T.; Pych, W. (1996) Icarus 124, 134-140.] [Torppa, J.; Hentunen, V.-P.; Paakkonen, P.; Kehusmaa, P.; Muinonen, K. (2008) Icarus 198, 91-107.] [Pilcher, F.; Jardine, D. (2009) Minor Planet Bul. 36, 52-54.] [Oey, J. (2010) Minor Planet Bul. 37, 135-136.] [Behrend, R. (2011) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Pilcher, F. (2012) Minor Planet Bul. 39, 57-60.] geometric albedo albedo 0.0543   0.005 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19 B-V BV .687 mag .021 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=3; phase (min.=7.43, mean=11.51, max.=13.73) deg. U-B UB .317 mag .021 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=3; phase (min.=7.43, mean=11.51, max.=13.73) deg. Tholen spectral type spec_T C   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 2 color indices SMASSII spectral type spec_B Cb   n/a EAR-A-5-DDR-TAXONOMY-V4.0 based on a high-resolution spectrum by Xu et al. (1995) or Bus and Binzel (2002) 31 Euphrosyne          Discovered 1854-Sep-01 by Ferguson, J. at Washington Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  A907 GP = A918 GB  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-21 08:44 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin