+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   305231 (2007 XR18) Classification: Main-belt Asteroid          SPK-ID: 2305231 [ 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 9 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1153964860310115 5.7143e-08   a 2.708078620342717 2.2655e-08 au q 2.395575863659458 1.4516e-07 au i 12.20075988984796 3.9679e-06 deg node 270.134972650719 2.7695e-05 deg peri 89.0863559361219 4.6666e-05 deg M 353.0304544952125 3.0241e-05 deg tp 2459032.013184120242 (2020-Jul-01.51318412) 0.00013659 TDB period 1627.759841082061 4.46 2.0426e-05 5.592e-08 d yr n .2211628465785765 2.7753e-09 deg/d Q 3.020581377025976 2.5269e-08 au   Orbit Determination Parameters    # obs. used (total)      347      data-arc span      6596 days (18.06 yr)      first obs. used      2002-10-06      last obs. used      2020-10-27      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .47574      source      ORB      producer      Otto Matic      solution date      2020-Nov-11 19:12:52   Additional Information  Earth MOID = 1.43005 au   Jupiter MOID = 2.44949 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 16.0   n/a MPO433966   305231 (2007 XR18)          Discovered 2007-Dec-13 by OAM at Costitx Reference: 20111110/Numbers.arc Last Updated: 2011-11-14 [ 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 1939-May-19 07:18 00:27 Iris 0.046421501099224 0.0463742606886673 0.0464687436814333 2.84215521513964 2.84215517156778 2429402.803953018 27.304218855681 2405.3054309083 103.134353356025 -11.9875829043654 14251.6531259384 T 9 CATAB v2.0f-lin.ifort 2020-Nov-11 19:12:54 2020-Nov-11 19:12 2146-Jun-21 23:43 00:04 Europ 0.039182966907033 0.0391500922284436 0.0392161108837149 6.52929858879244 6.52929854724848 2505042.488136603 3.49700647998871 5388.21428904968 100.845146913865 72.2477194566462 55343.7598888929 T 9 CATAB v2.0f-lin.ifort 2020-Nov-11 19:12:54 2020-Nov-11 19:12 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2020-Nov-28 00:39 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin