+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   9181 (1991 NP2) Classification: Main-belt Asteroid          SPK-ID: 2009181 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: MPO130058 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 0.1487567 n/a   a 2.3171670 n/a AU q 1.9724729 n/a AU i 6.84585 n/a deg node 317.49560 n/a deg peri 350.13369 n/a deg M 58.37559 n/a deg tp 2456191.5880775 (2012-Sep-21.08807750) n/a JED period 1288.3517257 3.53 n/a n/a d yr n 0.27942680 n/a deg/d Q 2.6618611 n/a AU   Orbit Determination Parameters    # obs. used (total)      528      first obs. used      1977-??-??      last obs. used      2007-12-08      # oppositions      13      planetary ephem.      DE403      condition code      0      fit RMS      0.53      data source      MPC:mpn      producer      MPCW   Additional Information  T_jup = 3.556  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 13.8 mag n/a PDS3 (MPC 32420)   9181 (1991 NP2)          Discovered 1991-Jul-14 by Holt, H. E. at Palomar (675) Reference: 19980910/Numbers.arc Last Updated: 2004-04-19 Alternate Designations  1991 NP2 = 1977 PB2 = 1991 PD3  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-21 03:19 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin