+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   120725 (1997 SL18) Classification: Main-belt Asteroid          SPK-ID: 2120725 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 18 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1707075479770129 4.0553e-08   a 2.345084831449856 1.0835e-08 au q 1.944761150074965 9.627e-08 au i 5.985354751881934 6.3607e-06 deg node 348.5551286175898 4.28e-05 deg peri 92.82320415573 4.7797e-05 deg M 97.82249920769061 1.8414e-05 deg tp 2458844.071423102193 (2019-Dec-26.57142310) 6.7025e-05 TDB period 1311.705269467524 3.59 9.0907e-06 2.489e-08 d yr n .2744518973733628 1.9021e-09 deg/d Q 2.745408512824748 1.2685e-08 au   Orbit Determination Parameters    # obs. used (total)      489      data-arc span      8225 days (22.52 yr)      first obs. used      1997-08-11      last obs. used      2020-02-17      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .53138      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 17:07:51   Additional Information  Earth MOID = .971032 au   Jupiter MOID = 2.49957 au   T_jup = 3.535  [ hide covariance matrix ] Orbital Elements at Epoch 2456854.5 (2014-Jul-16.0) TDB Reference: JPL 18 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .169610950311268 4.0457e-08   q 1.947896973656222 9.5908e-08 au tp 2456218.951024328807 (2012-Oct-18.45102433) 7.0185e-05 TDB node 348.6404978895852 4.2743e-05 deg peri 92.65690778250693 4.786e-05 deg i 5.98937515976075 6.363e-06 deg   Orbit Determination Parameters    # obs. used (total)      489      data-arc span      8225 days (22.52 yr)      first obs. used      1997-08-11      last obs. used      2020-02-17      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .53138      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 17:07:51   Additional Information  Jupiter MOID = 2.49957 au   T_jup = 3.535  Orbit Covariance (6×6)   e q tp node peri i e 1.636737638968681E-15 -3.863279798801572E-15 5.521932140595991E-13 -3.668981843656673E-16 1.978523598959592E-13 -4.636569719434315E-15 q -3.863279798801572E-15 9.198429029351727E-15 -1.447876098230572E-12 1.760159185932189E-15 -5.020734814671072E-13 1.129863211903198E-14 tp 5.521932140595991E-13 -1.447876098230572E-12 4.925941807581788E-9 -1.163387274773671E-11 1.520790865101557E-9 -7.039135063566647E-13 node -3.668981843656673E-16 1.760159185932189E-15 -1.163387274773671E-11 1.82692343745685E-9 -1.819612627145664E-9 -2.307609929884283E-11 peri 1.978523598959592E-13 -5.020734814671072E-13 1.520790865101557E-9 -1.819612627145664E-9 2.290573906518484E-9 2.267867789013992E-11 i -4.636569719434315E-15 1.129863211903198E-14 -7.039135063566647E-13 -2.307609929884283E-11 2.267867789013992E-11 4.0487398263643E-11 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 16.68   n/a E2021B55   120725 (1997 SL18)          Discovered 1997-Sep-28 by Spacewatch at Kitt Peak Reference: 20060314/Numbers.arc Last Updated: 2006-03-23 Alternate Designations  1997 SL18 = 2001 TE39  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Apr-16 18:32 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin