+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2813 Zappala (1981 WZ) Classification: Main-belt Asteroid          SPK-ID: 2002813 [ 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 45 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1536041590859079 3.7924e-08   a 3.13486483036697 1.502e-08 au q 2.653336554250464 1.2397e-07 au i 14.76254852847513 4.2811e-06 deg node 231.7781499772165 1.3405e-05 deg peri 247.4488375684992 1.975e-05 deg M 314.2043722116964 1.4954e-05 deg tp 2459458.398117697001 (2021-Aug-31.89811770) 8.4711e-05 TDB period 2027.340312924649 5.55 1.4571e-05 3.989e-08 d yr n .1775725553844794 1.2762e-09 deg/d Q 3.616393106483475 1.7328e-08 au   Orbit Determination Parameters    # obs. used (total)      2881      data-arc span      26228 days (71.81 yr)      first obs. used      1949-03-29      last obs. used      2021-01-18      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .38634      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 01:05:49   Additional Information  Earth MOID = 1.71089 au   Jupiter MOID = 1.82565 au   T_jup = 3.143  [ 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 11.01   n/a E2021B10   diameter diameter 32.040 km 0.085 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 18.231 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Franco, L.; Klinglesmith III, D.A.; Marchini, A. (2016) Minor Planet Bull. 43, 203-204.] geometric albedo albedo 0.044   0.007 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)   SMASSII spectral type spec_B T   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) 2813 Zappala (1981 WZ)          Discovered 1981-Nov-24 by Bowell, E. at Flagstaff (AM) Discovered at the Anderson Mesa station, which is operated by the Lowell Observatory. Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1981 WZ = 1931 VZ = 1949 FC = 1964 TH = 1979 OS14  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Feb-28 17:17 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin