+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   15731 (1990 UW2) Classification: Main-belt Asteroid          SPK-ID: 2015731 [ 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 32 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1145176047599607 4.119e-08   a 3.190507229036802 2.1095e-08 au q 2.825137983198168 1.2817e-07 au i 7.102955545834807 4.1901e-06 deg node 82.38542756046208 3.6125e-05 deg peri 240.0389996298533 4.1082e-05 deg M 136.8733996957113 2.0686e-05 deg tp 2458209.084448356683 (2018-Mar-31.58444836) 0.00011873 TDB period 2081.555650878752 5.70 2.0644e-05 5.652e-08 d yr n .172947574016588 1.7152e-09 deg/d Q 3.555876474875436 2.3511e-08 au   Orbit Determination Parameters    # obs. used (total)      1779      data-arc span      10933 days (29.93 yr)      first obs. used      1990-10-16      last obs. used      2020-09-21      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .4781      source      ORB      producer      Otto Matic      solution date      2020-Oct-22 16:41:26   Additional Information  Earth MOID = 1.82107 au   Jupiter MOID = 1.74851 au   T_jup = 3.175  [ 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 13.2   n/a MPO452393   diameter diameter 12.342 km 0.233 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.051   0.010 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   15731 (1990 UW2)          Discovered 1990-Oct-16 by Oak Ridge Observatory at Harvard Reference: 20000726/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1990 UW2 = 1999 FF25  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2020-Oct-28 01:07 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin