+ 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 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 17 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .06883977882294247 5.3079e-08   a 2.794433651886594 2.6665e-08 au q 2.602065457355334 1.4386e-07 au i 3.488238818510733 5.6355e-06 deg node 237.5771897681255 7.7511e-05 deg peri 166.3334503720732 8.6418e-05 deg M 276.3980435379879 4.3273e-05 deg tp 2459596.735215575177 (2022-Jan-17.23521557) 0.00020863 TDB period 1706.236117475074 4.67 2.4422e-05 6.686e-08 d yr n .2109907276682995 3.02e-09 deg/d Q 2.986801846417855 2.8501e-08 au   Orbit Determination Parameters    # obs. used (total)      396      data-arc span      7484 days (20.49 yr)      first obs. used      1998-12-08      last obs. used      2019-06-05      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .62849      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 15:37:06   Additional Information  Earth MOID = 1.61007 au   Jupiter MOID = 2.29983 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 17 CATAB v2.0f-lin.ifort 2021-Apr-13 15:37:07 2021-Apr-13 15:37 Alternate Designations  1998 XG18 = 2002 RR115  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-20 07:03 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin