+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   249609 (1999 RL161) Classification: Main-belt Asteroid          SPK-ID: 2249609 [ 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 13 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1456636910877158 5.5644e-08   a 2.35275457677606 1.5176e-08 au q 2.010043660899343 1.3711e-07 au i 6.971014560865595 5.7371e-06 deg node 194.1571931963394 3.9871e-05 deg peri 149.0024997764689 4.3132e-05 deg M 266.7453415130379 1.826e-05 deg tp 2459341.953369270522 (2021-May-07.45336927) 6.8302e-05 TDB period 1318.145548241685 3.61 1.2753e-05 3.492e-08 d yr n .2731109629586924 2.6424e-09 deg/d Q 2.695465492652778 1.7386e-08 au   Orbit Determination Parameters    # obs. used (total)      288      data-arc span      7554 days (20.68 yr)      first obs. used      1999-08-22      last obs. used      2020-04-27      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .5638      source      ORB      producer      Otto Matic      solution date      2020-May-21 13:45:41   Additional Information  Earth MOID = 1.0065 au   Jupiter MOID = 2.72402 au   T_jup = 3.532  [ 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 16.8   n/a MPO427417   249609 (1999 RL161)          Discovered 1999-Sep-09 by LINEAR at Socorro Reference: 20100923/Numbers.arc Last Updated: 2010-09-27 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2020-Jul-12 18:52 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin