+ 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 2459000.5 (2020-May-31.0) TDB Reference: JPL 38 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .04856573112650182 3.0524e-08   a 2.860814264041201 1.0041e-08 au q 2.721876727690915 8.6178e-08 au i 1.779948928088451 4.2485e-06 deg node 184.24210398144 0.00010478 deg peri 248.8379048588911 0.00011504 deg M 75.8190122581351 4.5929e-05 deg tp 2458628.272425675707 (2019-May-24.77242568) 0.0002258 TDB period 1767.392145660239 4.84 9.305e-06 2.548e-08 d yr n .2036899399400217 1.0724e-09 deg/d Q 2.999751800391487 1.0529e-08 au   Orbit Determination Parameters    # obs. used (total)      3204      data-arc span      32368 days (88.62 yr)      first obs. used      1931-10-31      last obs. used      2020-06-13      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .41998      source      ORB      producer      Otto Matic      solution date      2020-Jun-23 15:24:28   Additional Information  Earth MOID = 1.73714 au   Jupiter MOID = 2.13218 au   T_jup = 3.299  [ 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 11.5   n/a MPO452172   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-Jan-26 13:32 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin