+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   393P/Spacewatch-Hill Classification: Jupiter-family Comet          SPK-ID: 1003044 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2455867.5 (2011-Nov-02.0) TDB Reference: JPL 20 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1196916026361578 6.7379e-07   a 4.77344170429677 2.5712e-07 au q 4.202100816619217 3.188e-06 au i 16.80709420337157 4.4276e-05 deg node 36.41113599538443 5.2857e-05 deg peri 328.57811875 0.00049999 deg M 84.07626214243476 0.00038039 deg tp 2454977.854971097659 (2009-May-26.35497110) 0.0040313 TDB period 3809.30600675688 10.43 0.00030778 8.427e-07 d yr n .09450540317880432 7.6357e-09 deg/d Q 5.344782591974323 2.8789e-07 au   Orbit Determination Parameters    # obs. used (total)      140      data-arc span      4103 days (11.23 yr)      first obs. used      2009-09-17      last obs. used      2020-12-11      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .65431      source      ORB      producer      Otto Matic      solution date      2021-Jan-14 17:13:24   Additional Information  Earth MOID = 3.21395 au   Jupiter MOID = .186994 au   T_jup = 2.911  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes comet total magnitude M1 7.6   0.7 20 from 83 observations, assumed slope, autocmod 2.8 comet total magnitude slope K1 16.75   n/a 20 autocmod 2.8 comet nuclear magnitude M2 14.7   0.6 20 from 43 observations, autocmod 2.8 comet nuclear magnitude slope K2 5.   n/a 20 autocmod 2.8 comet nuclear phase coefficient PC 0.03   n/a 20 autocmod 2.8 [ show close-approach data ] Alternate Designations  Perihelion  Year (est.)  New-Style  Desig Roman  Numeral  Year/  Letter   2019.8   393P/2019 S5         2009.4   393P/2009 SK280        [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] 2021-Feb-25 15:46 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin