+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   153 Hilda Classification: Outer Main-belt Asteroid          SPK-ID: 2000153 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: JPL 1 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1385340320121796 5.8764e-08   a 3.972508143156242 3.2618e-08 AU q 3.422180572883591 2.3566e-07 AU i 7.827752903512319 6.8696e-06 deg node 228.1741599236478 5.0831e-05 deg peri 38.79357064528941 5.725e-05 deg M 262.2615603445089 3.1547e-05 deg tp 2457185.660642544986 (2015-Jun-12.16064255) 0.00025907 JED period 2891.982236595023 7.92 3.5619e-05 9.752e-08 d yr n .1244820924017357 1.5332e-09 deg/d Q 4.522835713428893 3.7137e-08 AU   Orbit Determination Parameters    # obs. used (total)      1385      data-arc span      43115 days (118.04 yr)      first obs. used      1895-03-30      last obs. used      2013-04-15      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .6377      data source      ORB      producer      Otto Matic      solution date      2013-Apr-29 12:32:41   Additional Information  Earth MOID = 2.41165 AU   T_jup = 3.024  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 7.48 mag n/a IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19 diameter diameter 170.63 km 3.3 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19 rotation period rot_per 5.9587 h n/a Asteroid Lightcurve DataBase (Rev. 2013-May-01) Published Reference List: [Shevchenko, V.G.; Tungalag, N.; Chiorny, V.G.; Gaftonyuk, N.M.; et al. (2008) ACM 2008, 8106.] [Shevchenko, V.G.; Tungalag, N.; Chiorny, V.G.; Gaftonyuk, N.M.; et al. (2009) Plan. Space Sci. 57, 1514-1520.] geometric albedo albedo 0.0618   0.002 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19 B-V BV .669 mag .020 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=6; phase (min.=2.32, mean=7.15, max.=12.62) deg. U-B UB .243 mag .035 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=6; phase (min.=2.32, mean=7.15, max.=12.62) deg. Tholen spectral type spec_T P   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo SMASSII spectral type spec_B X   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) 153 Hilda          Discovered 1875-Nov-02 by Palisa, J. at Pola Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1935 GD  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2013-Jun-19 03:35 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin