+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   18356 (1990 SF1) Classification: Main-belt Asteroid          SPK-ID: 2018356 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: MPO231543 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 0.1734047 n/a   a 2.8470275 n/a AU q 2.3533396 n/a AU i 3.59873 n/a deg node 265.21549 n/a deg peri 145.86447 n/a deg M 223.45552 n/a deg tp 2457066.0145886 (2015-Feb-12.51458860) n/a JED period 1754.6315449 4.80 n/a n/a d yr n 0.20517128 n/a deg/d Q 3.3407154 n/a AU   Orbit Determination Parameters    # obs. used (total)      658      first obs. used      1976-??-??      last obs. used      2012-05-21      # oppositions      14      planetary ephem.      DE403      condition code      0      fit RMS      0.57      data source      MPC:mpn      producer      MPCLINUX   Additional Information  T_jup = 3.282  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 13.6 mag n/a PDS3 (MPO 5169)   18356 (1990 SF1)          Discovered 1990-Sep-16 by Holt, H. E. at Palomar (675) Reference: 20001111/Numbers.arc Last Updated: 2004-04-19 Alternate Designations  1990 SF1 = 1976 YW = 1994 NG11  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-24 08:37 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin