+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   881 Athene (A917 OD) Classification: Main-belt Asteroid          SPK-ID: 2000881 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 39 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2055895322658464 1.6383e-08   a 2.613852095332594 8.2769e-09 au q 2.076471465641064 4.2435e-08 au i 14.18996159057637 4.2515e-07 deg node 277.0318732024559 8.878e-07 deg peri 41.35209470267508 3.4991e-06 deg M 167.8955961225969 4.2262e-06 deg tp 2458480.625574368633 (2018-Dec-28.12557437) 1.5918e-05 TDB period 1543.547294939518 4.23 7.3316e-06 2.007e-08 d yr n .2332290051495352 1.1078e-09 deg/d Q 3.151232725024125 9.9786e-09 au   Orbit Determination Parameters    # obs. used (total)      2806      data-arc span      37857 days (103.65 yr)      first obs. used      1917-07-22      last obs. used      2021-03-15      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .41481      source      ORB      producer      Otto Matic      solution date      2021-Apr-12 11:34:47   Additional Information  Earth MOID = 1.08125 au   Jupiter MOID = 2.17811 au   T_jup = 3.336  [ 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 11.89   n/a E2021B10   diameter diameter 12.153 km 0.101 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 13.895 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Behrend, R. (2006) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Behrend, R. (2010) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Durech, J.; Hanus, J.; Oszkiewsicz, D.; Vanco, R. (2016) Astron. Astrophys. 587, A48.] [Hanus, J.; Durech, J.; Oszkiewicz, D.A.; Behrend, R.; et al. (2016) Astron. Astrophys. 586, A108.] geometric albedo albedo 0.237   0.039 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   881 Athene (A917 OD)          Discovered 1917-Jul-22 by Wolf, M. at Heidelberg Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-23 00:52 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin