+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   101507 (1998 XG18) Classification: Main-belt Asteroid          SPK-ID: 2101507 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 16 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .06968460834200607 5.34e-08   a 2.793956933132564 2.5705e-08 au q 2.599261138522789 1.4598e-07 au i 3.491951374210407 5.7111e-06 deg node 237.6670636159177 7.8869e-05 deg peri 166.2228018714168 8.7525e-05 deg M 234.3087244499105 4.2608e-05 deg tp 2459596.066993382133 (2022-Jan-16.56699338) 0.00020694 TDB period 1705.799520923195 4.67 2.354e-05 6.445e-08 d yr n .2110447303943223 2.9125e-09 deg/d Q 2.988652727742339 2.7496e-08 au   Orbit Determination Parameters    # obs. used (total)      389      data-arc span      7450 days (20.40 yr)      first obs. used      1998-12-08      last obs. used      2019-05-02      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .63127      source      ORB      producer      Otto Matic      solution date      2020-Nov-12 20:00:11   Additional Information  Earth MOID = 1.60826 au   Jupiter MOID = 2.301 au   T_jup = 3.322  [ 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 15.8   n/a MPO432542   diameter diameter 4.386 km 0.955 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.048   0.012 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   101507 (1998 XG18)          Discovered 1998-Dec-08 by Spacewatch at Kitt Peak Reference: 20051019/Numbers.arc Last Updated: 2005-10-26 [ hide close-approach data ] Close-Approach Data   ...sorted by Date/Time (TDB) Date/Time (TDB) Time Uncertainty (days_HH:MM) Body Nominal Distance (au) Minimum Distance (au) Maximum Distance (au) V-relative (km/s) V-infinity (km/s) JD (TDB) Time Uncertainty (minutes) Semi-major axis (km) Semi-minor axis (km) range-LOV angle (deg) N-sigma BP Orbit Ref. Reference Modified 1969-Apr-01 16:36 00:01 Psych 0.0297654478631333 0.0297566253898703 0.0297742712520352 2.04901913052401 2.04901893214544 2440313.191438470 1.42092940319353 510.868125221701 53.9883841780795 -31.0166951822026 43002.8305372696 T 16 CATAB v2.0f-lin.ifort 2020-Nov-12 20:00:12 2020-Nov-12 20:00 Alternate Designations  1998 XG18 = 2002 RR115  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-21 01:22 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin