+ 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 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 37 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1145772903693147 4.0787e-08   a 3.190547614740823 1.8821e-08 au q 2.824983314249539 1.2778e-07 au i 7.102306255705432 3.752e-06 deg node 82.38106473547758 3.4269e-05 deg peri 240.1148353649497 3.8508e-05 deg M 171.3716303784805 1.9891e-05 deg tp 2458209.593448013803 (2018-Apr-01.09344801) 0.00011245 TDB period 2081.595173758851 5.70 1.8419e-05 5.043e-08 d yr n .1729442902915307 1.5303e-09 deg/d Q 3.556111915232107 2.0977e-08 au   Orbit Determination Parameters    # obs. used (total)      1979      data-arc span      11108 days (30.41 yr)      first obs. used      1990-10-16      last obs. used      2021-03-15      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .46766      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 01:07:30   Additional Information  Earth MOID = 1.81899 au   Jupiter MOID = 1.74819 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 13.21   n/a E2021B10   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 ] 2021-Apr-16 09:25 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin