+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   120906 (1998 SL39) Classification: Main-belt Asteroid          SPK-ID: 2120906 [ 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 22 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1080327874535582 4.8891e-08   a 3.057212337317457 2.3951e-08 au q 2.726933166679645 1.5665e-07 au i 1.388668375526175 5.4492e-06 deg node 168.6052862590544 0.00017214 deg peri 339.7599719247822 0.00017369 deg M 269.1915570976414 2.5101e-05 deg tp 2459693.004905117702 (2022-Apr-23.50490512) 0.00013907 TDB period 1952.481070873725 5.35 2.2944e-05 6.282e-08 d yr n .1843807888180457 2.1667e-09 deg/d Q 3.38749150795527 2.6538e-08 au   Orbit Determination Parameters    # obs. used (total)      496      data-arc span      8121 days (22.23 yr)      first obs. used      1998-09-13      last obs. used      2020-12-07      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .52499      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 17:08:43   Additional Information  Earth MOID = 1.73824 au   Jupiter MOID = 1.61219 au   T_jup = 3.226  [ hide covariance matrix ] Orbital Elements at Epoch 2457479.5 (2016-Apr-01.0) TDB Reference: JPL 22 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1055376629465699 4.9661e-08   q 2.735432555889799 1.5874e-07 au tp 2457745.391813888979 (2016-Dec-22.89181389) 0.00013069 TDB node 168.6194794736029 0.00017212 deg peri 340.8679908036332 0.00017371 deg i 1.387757280367088 5.4532e-06 deg   Orbit Determination Parameters    # obs. used (total)      496      data-arc span      8121 days (22.23 yr)      first obs. used      1998-09-13      last obs. used      2020-12-07      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .52499      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 17:08:43   Additional Information  Jupiter MOID = 1.61219 au   T_jup = 3.226  Orbit Covariance (6×6)   e q tp node peri i e 2.466199636047283E-15 -7.816251301588318E-15 8.174552543966207E-13 1.451653979937319E-15 2.340980758615571E-13 6.460395374951192E-17 q -7.816251301588318E-15 2.519857625729589E-14 -1.463048426526414E-12 1.317032700646081E-15 -5.580225570012358E-13 2.220414038449357E-16 tp 8.174552543966207E-13 -1.463048426526414E-12 1.707974091463044E-8 -7.352099024720899E-12 3.070944554341027E-9 1.988323216403244E-12 node 1.451653979937319E-15 1.317032700646081E-15 -7.352099024720899E-12 2.962585798086494E-8 -2.961818630759963E-8 2.016755017052631E-10 peri 2.340980758615571E-13 -5.580225570012358E-13 3.070944554341027E-9 -2.961818630759963E-8 3.017439915861806E-8 -2.012617667893223E-10 i 6.460395374951192E-17 2.220414038449357E-16 1.988323216403244E-12 2.016755017052631E-10 -2.012617667893223E-10 2.973719998074142E-11 [ 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 15.6   n/a MPO453679   120906 (1998 SL39)          Discovered 1998-Sep-23 by Spacewatch at Kitt Peak Reference: 20060314/Numbers.arc Last Updated: 2006-03-23 [ show close-approach data ] Alternate Designations  1998 SL39 = 2004 TU54  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-21 08:15 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin