+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   38P/Stephan-Oterma Classification: Halley-type Comet*          SPK-ID: 1000089 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] alternate orbits: [epoch=2018-May-24.0] 22 (default) [epoch=1942-Dec-27.0] SAO/1942 [epoch=1867-Feb-03.0] SAO/1867 Orbital Elements at Epoch 2458262.5 (2018-May-24.0) TDB Reference: JPL 22 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .859286285876197 2.1965e-08   a 11.28891421895193 2.7664e-08 au q 1.588505048173736 2.4538e-07 au i 18.3529465228447 6.7826e-06 deg node 78.00036419278668 1.5579e-05 deg peri 359.5886765534911 2.6576e-05 deg M 355.5568622320152 1.0604e-06 deg tp 2458433.487343535866 (2018-Nov-10.98734354) 4.0417e-05 TDB period 13854.04794702775 37.93 5.0925e-05 1.394e-07 d yr n .02598518507922694 9.5518e-11 deg/d Q 20.98932338973012 5.1436e-08 au Additional Model Parameters  Parameter Value Uncertainty (1-sigma)  A2 [EST] -2.68703931765036E-11 2.055E-13   Orbit Determination Parameters    # obs. used (total)      3265      data-arc span      28321 days (77.54 yr)      first obs. used      1942-11-06      last obs. used      2020-05-21      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .47939      source      ORB      producer      Javier Roa      solution date      2020-May-27 08:45:01   Additional Information  Earth MOID = .604127 au   Jupiter MOID = 1.33239 au   T_jup = 1.891  [ 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 comet total magnitude M1 11.5   01. 22 2 parameter fit from 1092 observations, autocmod 2.8 comet total magnitude slope K1 9.5   n/a 22 autocmod 2.8 comet nuclear magnitude M2 13.4   0.6 22 from 1783 observations, autocmod 2.8 comet nuclear magnitude slope K2 5.   n/a 22 autocmod 2.8 comet nuclear phase coefficient PC 0.03   n/a 22 autocmod 2.8 38P/Stephan-Oterma          Discovered 1867-Jan-22 by Coggia, Jerome E. at Marseilles Observatory, France Reference: comet.dis Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  Perihelion  Year (est.)  New-Style  Desig Roman  Numeral  Year/  Letter   1980.9   38P/1980 L2   1980 X   1980g   1943.0   38P/1942 V1   1942 IX     1867.1   38P/1867 B1   1867 I    [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-17 20:30 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin