+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   109902 (2001 SH21) Classification: Main-belt Asteroid          SPK-ID: 2109902 [ 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 20 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .05031480973812953 4.0848e-08   a 2.55307863430706 1.1048e-08 au q 2.424620968575417 1.0655e-07 au i 4.605037031816964 4.1372e-06 deg node 117.0071697647048 5.5084e-05 deg peri 258.2846062430011 6.9397e-05 deg M 206.5095420466393 4.3363e-05 deg tp 2459635.792304683588 (2022-Feb-25.29230468) 0.00018097 TDB period 1490.028974671413 4.08 9.6715e-06 2.648e-08 d yr n .2416060399626715 1.5682e-09 deg/d Q 2.681536300038704 1.1604e-08 au   Orbit Determination Parameters    # obs. used (total)      852      data-arc span      10657 days (29.18 yr)      first obs. used      1991-02-22      last obs. used      2020-04-27      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .58605      source      ORB      producer      Otto Matic      solution date      2020-May-20 19:10:40   Additional Information  Earth MOID = 1.42972 au   Jupiter MOID = 2.53664 au   T_jup = 3.433  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 15.6   n/a MPO268016   109902 (2001 SH21)          Discovered 2001-Sep-16 by LINEAR at Socorro Reference: 20051019/Numbers.arc Last Updated: 2005-10-26 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2020-Jul-05 11:59 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin