+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   11903 (1991 RD7) Classification: Main-belt Asteroid          SPK-ID: 2011903 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: MPO253448 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 0.1822345 n/a   a 2.5641137 n/a AU q 2.0968437 n/a AU i 16.33004 n/a deg node 3.76752 n/a deg peri 354.74691 n/a deg M 94.21762 n/a deg tp 2456008.0051477 (2012-Mar-21.50514770) n/a JED period 1499.6998101 4.11 n/a n/a d yr n 0.24004804 n/a deg/d Q 3.0313837 n/a AU   Orbit Determination Parameters    # obs. used (total)      731      first obs. used      1954-??-??      last obs. used      2013-02-03      # oppositions      15      planetary ephem.      DE403      condition code      0      fit RMS      0.50      data source      MPC:mpn      producer      MPCLINUX   Additional Information  T_jup = 3.354  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 13.1 mag n/a PDS3 (MPC 36247)   11903 (1991 RD7)          Discovered 1991-Sep-02 by McNaught, R. H. at Siding Spring (413) Reference: 19991026/Numbers.arc Last Updated: 2004-04-19 Alternate Designations  1991 RD7 = 1954 RW = 1987 SL21  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-24 21:55 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin