+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   100 Hekate (A868 NA) Classification: Main-belt Asteroid          SPK-ID: 2000100 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 40 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1695552885909357 3.9297e-08   a 3.089431762137787 1.1355e-08 au q 2.565602268126512 1.2369e-07 au i 6.431994780451404 4.4203e-06 deg node 127.1816270821434 3.7595e-05 deg peri 184.3863360475689 3.9884e-05 deg M 319.3062917777115 1.5383e-05 deg tp 2459224.702836976048 (2021-Jan-10.20283698) 8.5169e-05 TDB period 1983.427533084085 5.43 1.0935e-05 2.994e-08 d yr n .18150398438819 1.0007e-09 deg/d Q 3.613261256149063 1.328e-08 au   Orbit Determination Parameters    # obs. used (total)      2977      data-arc span      54721 days (149.82 yr)      first obs. used      1871-01-15      last obs. used      2020-11-10      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .42827      source      ORB      producer      Otto Matic      solution date      2020-Dec-18 01:51:02   Additional Information  Earth MOID = 1.55137 au   Jupiter MOID = 1.66971 au   T_jup = 3.193  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 7.6   n/a MPO473761 IRAS observations used: 23 diameter diameter 85.734 km 1.961 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 27.066 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Behrend, R. (2005) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Galad, A.; Vilagi, J.; Kornos, L.; Gajdos, S. (2009) Minor Planet Bull. 36, 116-118.] [Behrend, R. (2019) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] geometric albedo albedo 0.205   0.010 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   B-V BV 0.838   0.025 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=3; phase (min.=2.98, mean=5.97, max.=11.64) deg. U-B UB 0.363   0.049 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=3; phase (min.=2.98, mean=5.97, max.=11.64) deg. Tholen spectral type spec_T S   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 2 color indices 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) 100 Hekate (A868 NA)          Discovered 1868-Jul-11 by Watson, J. C. at Ann Arbor Independent discovery July 18 by C. Wolf, Paris, was announced first. Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  A868 NA = 1955 QA  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-18 19:54 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin