+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   18347 (1989 WU) Classification: Main-belt Asteroid          SPK-ID: 2018347 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 31 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .155460037777699 3.3026e-08   a 2.231885984733563 6.1024e-09 au q 1.884916905231366 7.3518e-08 au i 4.959816861333669 3.6955e-06 deg node 270.1802137285698 4.4169e-05 deg peri 174.946168096234 4.6657e-05 deg M 42.33382934395619 1.2926e-05 deg tp 2458857.284016952669 (2020-Jan-08.78401695) 4.3836e-05 TDB period 1217.885428651872 3.33 4.9949e-06 1.368e-08 d yr n .2955943075848268 1.2123e-09 deg/d Q 2.578855064235759 7.0511e-09 au   Orbit Determination Parameters    # obs. used (total)      1845      data-arc span      11132 days (30.48 yr)      first obs. used      1989-11-20      last obs. used      2020-05-13      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .45009      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 02:15:32   Additional Information  Earth MOID = .90119 au   Jupiter MOID = 2.62511 au   T_jup = 3.620  [ hide covariance matrix ] Orbital Elements at Epoch 2456653.5 (2013-Dec-27.0) TDB Reference: JPL 31 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .154889869734416 3.2948e-08   q 1.886033421642105 7.3292e-08 au tp 2456420.618155545042 (2013-May-08.11815555) 4.7163e-05 TDB node 270.2533104579849 4.4222e-05 deg peri 174.7112471718402 4.6739e-05 deg i 4.956125162068345 3.6937e-06 deg   Orbit Determination Parameters    # obs. used (total)      1845      data-arc span      11132 days (30.48 yr)      first obs. used      1989-11-20      last obs. used      2020-05-13      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .45009      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 02:15:32   Additional Information  Jupiter MOID = 2.62511 au   T_jup = 3.620  Orbit Covariance (6×6)   e q tp node peri i e 1.085564624753751E-15 -2.408901908785182E-15 -1.199476182487603E-13 -2.951501303419071E-15 -5.444127320151262E-14 -8.502809180200092E-16 q -2.408901908785182E-15 5.37171767714542E-15 1.734347925938742E-13 5.54651976439196E-15 9.360518000064555E-14 2.006785163073746E-15 tp -1.199476182487603E-13 1.734347925938742E-13 2.224356884774073E-9 7.218746489366436E-12 7.256626642493557E-10 -1.944814839374297E-12 node -2.951501303419071E-15 5.54651976439196E-15 7.218746489366436E-12 1.955559863063243E-9 -1.945229325491374E-9 1.169215324457939E-11 peri -5.444127320151262E-14 9.360518000064555E-14 7.256626642493557E-10 -1.945229325491374E-9 2.184543806675852E-9 -1.22682359636204E-11 i -8.502809180200092E-16 2.006785163073746E-15 -1.944814839374297E-12 1.169215324457939E-11 -1.22682359636204E-11 1.364318669910085E-11 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 14.2   n/a MPO412322   diameter diameter 3.988 km 0.069 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.255   0.043 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   18347 (1989 WU)          Discovered 1989-Nov-20 by Oohira at Oohira Reference: 20001111/Numbers.arc Last Updated: 2004-04-19 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Jan-18 12:00 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin