+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   18374 (1991 RA18) Classification: Main-belt Asteroid          SPK-ID: 2018374 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: JPL 1 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1327204366014482 7.8444e-08   a 2.688820498838957 2.9883e-08 AU q 2.331959068290127 2.0945e-07 AU i 3.046799227903231 8.2775e-06 deg node 215.6232637348657 0.00011544 deg peri 153.7933318827558 0.00011798 deg M 309.8315926559359 2.8643e-05 deg tp 2456624.923822789653 (2013-Nov-28.42382279) 0.00012981 JED period 1610.427368167873 4.41 2.6847e-05 7.35e-08 d yr n .2235431458231857 3.7266e-09 deg/d Q 3.045681929387787 3.3849e-08 AU   Orbit Determination Parameters    # obs. used (total)      685      data-arc span      7881 days (21.58 yr)      first obs. used      1991-09-13      last obs. used      2013-04-11      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .54663      data source      ORB      producer      Otto Matic      solution date      2013-Apr-29 14:18:44   Additional Information  Earth MOID = 1.33129 AU   T_jup = 3.358  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 14.6 mag n/a PDS3 (MPO 5174)   18374 (1991 RA18)          Discovered 1991-Sep-13 by Holt, H. E. at Palomar (675) Reference: 20001111/Numbers.arc Last Updated: 2004-04-19 Alternate Designations  1991 RA18 = 1998 FJ140  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-21 13:29 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin