+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   15 Eunomia Classification: Main-belt Asteroid          SPK-ID: 2000015 [ 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 68 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1880098209787783 2.8345e-08   a 2.642681236182935 3.2135e-09 AU q 2.145831210064205 7.4747e-08 AU i 11.7388827863933 2.5928e-06 deg node 293.1943683218409 1.4909e-05 deg peri 97.57373953213542 1.6373e-05 deg M 139.914939782588 6.8682e-06 deg tp 2455790.644159085321 (2011-Aug-17.14415909) 2.9452e-05 JED period 1569.154109421319 4.30 2.8621e-06 7.836e-09 d yr n .2294229724400764 4.1847e-10 deg/d Q 3.139531262301666 3.8177e-09 AU   Orbit Determination Parameters    # obs. used (total)      2066      data-arc span      58936 days (161.36 yr)      first obs. used      1851-09-02      last obs. used      2013-01-11      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .63477      data source      ORB      producer      Otto Matic      solution date      2013-Mar-29 14:26:34   Additional Information  Earth MOID = 1.18852 AU   T_jup = 3.340  [ 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 5.28 mag n/a IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 21 magnitude slope G 0.23   n/a PDS3 (MPC 17257) Fit diameter diameter 255.33 km 15.0 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 21 rotation period rot_per 6.083 h n/a Asteroid Lightcurve DataBase (Rev. 2013-May-01) Published Reference List: [Groeneveld, I.; Kuiper, G.P. (1954) Astrophys. J. 120, 200-220.] [Cailliate, C. (1956) Publ. Observ. Lyon 3, fasc. 28.] [Van Houten-Groeneveld, I.; van Houten, C.J. (1958) Astrophys. J. 127, 253-273.] [Cailliate, C. (1960) Bull. Astronomique XXIII, fasc. III.] [Scaltriti, F.; Zappala, V. (1975) Astron. Astrophys. Suppl. Ser. 19, 249-255.] [Chang, Y.C.; Zhou, X.-h.; Yang, X.-y.; Zhang, Y.-y.; et al. (1981) Acta Astron. Sin. 22, 169-173; Chin. Astron. Astrophys. 5, 434-437.] [Lupishko, D.F.; Belskaja, I.N.; Velichko, F.P. (1985) Vestn. Kharkov Univ. 278, 51-56.] [Magnusson, P. (1986) Icarus 68, 1-39.] [Melillo, F.J. (1986) Minor Planet Bul. 13, 21-22.] [Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R.; Greenberg, R.; et al. (1987) Icarus 70, 191-245.] [Lagerkvist, C.I.; Magnusson, P.; Williams, I.P.; Buontempo, M.E.; et al. (1988) Astron. Astrophys. Suppl. Ser. 73, 395-405.] [Drummond, J.D.; Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R. (1988) Icarus 76, 19-77.] [Lagerkvist, C.I.; Magnusson, P.; Williams, I.P.; Buontempo, M.E.; et al. (1989) Astron. Astrophys. Suppl. Ser. 78, 519-532.] [Magnusson, P. (1990) Icarus 85, 229-240.] [Drummond, J.D.; Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R. (1991) Icarus 89, 44-64.] [De Angelis, G. (1992) in Physical properties of small solar system bodies. A. Brahic, J.-C. Gerard, J. Surdej, eds. Universite de Liege, Institut d'Astrophysique, Liege, pp. 195-201.] [Michalowski, T. (1993) Icarus 106, 563-572.] [De Angelis, G. (1995) Planet. Space Sci. 43, 649-682.] [Kaasalainen, M.; Torppa, J.; Piironen, J. (2002) Icarus 159, 369-395.] [Nathues, A.; Mottola, S.; Kaasalainen, M.; Neukum, G. (2005) Icarus 175, 452-463.] geometric albedo albedo 0.2094   0.027 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 21 B-V BV .839 mag .015 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=23; phase (min.=3.66, mean=16.49, max.=25.91) deg. U-B UB .451 mag .019 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=15; phase (min.=6.04, mean=19.34, max.=25.91) deg. Tholen spectral type spec_T S   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo SMASSII spectral type spec_B S   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) 15 Eunomia          Discovered 1851-Jul-29 by De Gasparis, A. at Naples Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-22 17:27 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin