+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   993 Moultona (A923 AB) Classification: Main-belt Asteroid          SPK-ID: 2000993 [ 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 40 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .04863618943919679 3.0548e-08   a 2.860197043076355 9.9093e-09 au q 2.721087957855863 8.6161e-08 au i 1.780218901783902 4.2379e-06 deg node 184.239926683194 0.00010317 deg peri 248.5888191202507 0.00011309 deg M 116.8107176083335 4.4878e-05 deg tp 2458627.212400250603 (2019-May-23.71240025) 0.00022063 TDB period 1766.820203962681 4.84 9.1818e-06 2.514e-08 d yr n .2037558769095918 1.0589e-09 deg/d Q 2.999306128296847 1.0391e-08 au   Orbit Determination Parameters    # obs. used (total)      3324      data-arc span      32593 days (89.23 yr)      first obs. used      1931-10-31      last obs. used      2021-01-24      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .41557      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 00:51:34   Additional Information  Earth MOID = 1.73577 au   Jupiter MOID = 2.13267 au   T_jup = 3.300  [ 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 11.52   n/a E2021B10   diameter diameter 12.433 km 1.133 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)   rotation period rot_per 5.2712 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Behrend, R. (2014) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] geometric albedo albedo 0.315   0.033 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)   993 Moultona (A923 AB)          Discovered 1923-Jan-12 by Van Biesbroeck, G. at Williams Bay Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  A923 AB = 1928 BA = 1960 WD = 1964 PQ = 1967 CN  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Feb-25 20:00 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin