+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   18355 (1990 RN9) Classification: Main-belt Asteroid          SPK-ID: 2018355 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: MPO256999 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 0.2483687 n/a   a 2.6492083 n/a AU q 1.9912279 n/a AU i 10.90483 n/a deg node 304.56930 n/a deg peri 73.70529 n/a deg M 64.15164 n/a deg tp 2456119.8417216 (2012-Jul-11.34172160) n/a JED period 1574.9711190 4.31 n/a n/a d yr n 0.22857562 n/a deg/d Q 3.3071887 n/a AU   Orbit Determination Parameters    # obs. used (total)      504      first obs. used      1976-??-??      last obs. used      2013-03-02      # oppositions      13      planetary ephem.      DE403      condition code      0      fit RMS      0.52      data source      MPC:mpn      producer      MPCLINUX   Additional Information  T_jup = 3.322  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 13.2 mag n/a PDS3 (MPO 5169)   18355 (1990 RN9)          Discovered 1990-Sep-14 by Holt, H. E. at Palomar (675) Reference: 20001111/Numbers.arc Last Updated: 2004-04-19 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-21 19:57 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin