+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   C/2012 S1 (ISON) Classification: Hyperbolic Comet          SPK-ID: 1003203 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2456413.5 (2013-May-01.0) TDB Reference: JPL 55 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 1.000005095700877 1.6092e-08   a -2446.515869432519 7.7289 au q .01246671306154389 1.0063e-07 au i 62.16289448145616 0.00032658 deg node 295.6865417212286 5.5497e-05 deg peri 345.5411989977785 4.3516e-05 deg M -.001724786075348974 8.1729e-06 deg tp 2456625.264530258320 (2013-Nov-28.76453026) 7.9908e-05 TDB period n/a n/a n/a n/a d yr n 8.144829888390664E-6 3.8596e-08 deg/d Q n/a n/a au Additional Model Parameters  Parameter Value Uncertainty (1-sigma)  A1 [EST] 8.539073016664726E-8 2.168E-9 A2 [EST] 5.751266901683991E-9 6.145E-10   Orbit Determination Parameters    # obs. used (total)      6682      data-arc span      784 days (2.15 yr)      first obs. used      2011-09-30      last obs. used      2013-11-22      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      norm. resid. RMS      .57173      source      ORB      producer      Otto Matic      solution date      2020-Nov-11 11:00:42   Additional Information  Earth MOID = .0229939 au   Jupiter MOID = .68569 au   T_jup = 0.065  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes comet total magnitude M1 8.8   0.9 55 2 parameter fit from 1211 observations, autocmod 2.8 comet total magnitude slope K1 6.75   n/a 55 autocmod 2.8 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Close-Approach Data ] 2021-Jan-26 10:32 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin