+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   30785 Greeley (1988 PX) Classification: Mars-crossing Asteroid          SPK-ID: 2030785 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 15 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .3442211949252122 5.1568e-08   a 2.200889554917029 1.1495e-08 au q 1.443296722425071 1.1468e-07 au i 5.401881556517794 7.1242e-06 deg node 13.3868734292696 5.3189e-05 deg peri 308.9681640804747 5.4275e-05 deg M 326.1863352552095 1.6327e-05 deg tp 2459312.517414010452 (2021-Apr-08.01741401) 5.4783e-05 TDB period 1192.602734667365 3.27 9.3435e-06 2.558e-08 d yr n .3018607869454613 2.3649e-09 deg/d Q 2.958482387408987 1.5452e-08 au   Orbit Determination Parameters    # obs. used (total)      303      data-arc span      11599 days (31.76 yr)      first obs. used      1988-08-13      last obs. used      2020-05-16      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .5873      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 06:39:58   Additional Information  Earth MOID = .438108 au   Jupiter MOID = 2.40125 au   T_jup = 3.580  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 16.53   n/a E2021B10   30785 Greeley           Discovered 1988 Aug. 13 by C. S. Shoemaker and E. M. Shoemaker at Palomar. Ronald Greeley (b. 1939) has been involved in lunar and planetary studies since 1967. His current research focuses on understanding planetary surface processes and geological histories and involves a combination of spacecraft data analysis, laboratory experiments and geological field studies on the earth. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20030501/MPCPages.arc Last Updated: 2003-10-02 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-15 23:46 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin