+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   989 Schwassmannia (A922 WD) Classification: Main-belt Asteroid          SPK-ID: 2000989 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 40 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2504128688901185 1.357e-08   a 2.660283949720515 7.8282e-09 au q 1.994114613808665 3.5708e-08 au i 14.69156780012453 5.7971e-07 deg node 243.3850494039917 3.0831e-06 deg peri 165.543541471445 4.5281e-06 deg M 265.0446185753475 7.2482e-06 deg tp 2459814.530048086366 (2022-Aug-23.03004809) 3.3226e-05 TDB period 1584.858225549933 4.34 6.9954e-06 1.915e-08 d yr n .2271496555315432 1.0026e-09 deg/d Q 3.326453285632366 9.7885e-09 au   Orbit Determination Parameters    # obs. used (total)      2740      data-arc span      36018 days (98.61 yr)      first obs. used      1922-11-12      last obs. used      2021-06-23      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .3774      source      ORB      producer      Otto Matic      solution date      2021-Jul-08 11:48:46   Additional Information  Earth MOID = 1.00787 au   Jupiter MOID = 2.07071 au   T_jup = 3.295  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 11.93   n/a E2021B10   diameter diameter 12.630 km 0.124 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 107.85 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Benishek, V.; Pilcher, F.; Martinez, L. (2014) Minor Planet Bull. 41, 133.] geometric albedo albedo 0.306   0.064 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   989 Schwassmannia (A922 WD)          Discovered 1922-Nov-18 by Schwassmann, A. at Bergedorf Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  A922 WD = 1935 UE = 1935 UF  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Jul-29 23:01 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin