******************************************************************************* JPL/HORIZONS ISON (C/2012 S1) 2025-Dec-12 21:13:08 Rec #:90004181 (+COV) Soln.date: 2025-Nov-21_13:42:48 # obs: 6684 (2011-2013) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2456413.5 ! 2013-May-01.0000000 (TDB) RMSW= n.a. EC= 1.00000509491957 QR= .01246672509220626 TP= 2456625.2645311668 OM= 295.6865414817095 W= 345.5411966905318 IN= 62.16289620932959 A= -2446.893404476403 MA= -.001724386918197071ADIST= 9.999999E99 PER= 9.999999E99 N= 8.143E-6 ANGMOM= .002716272 DAN= .01267 DDN= .78735 L= 288.8208505 B= -12.7554438 MOID= .0229938 TP= 2013-Nov-28.7645311668 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= n.a. M1= 10.4 M2= n.a. k1= 4.5 k2= n.a. PHCOF= n.a. Comet non-gravitational force model (AMRAT=m^2/kg;A1-A3=au/d^2;DT=days;R0=au): AMRAT= 0. DT= 0. A1= 8.537815093994E-8 A2= 5.695189237595E-9 A3= 0. Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 COMET comments 1: soln ref.= JPL#57, data arc: 2011-09-30 to 2013-11-22 2: k1=4.5; ******************************************************************************* ******************************************************************************* Ephemeris / WWW_USER Fri Dec 12 21:13:09 2025 Pasadena, USA / Horizons ******************************************************************************* Target body name: ISON (C/2012 S1) {source: JPL#57} Center body name: Solar System Barycenter (0) {source: DE441} Center-site name: BODY CENTER ******************************************************************************* Start time : A.D. 1950-Jan-01 00:00:00.0000 TDB Stop time : A.D. 2050-Jan-01 00:00:00.0000 TDB Step-size : 100 calendar years ******************************************************************************* Center geodetic : 0.0, 0.0, 0.0 {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: 0.0, 0.0, 0.0 {E-lon(deg),Dxy(km),Dz(km)} Center radii : (undefined) Keplerian GM : 2.9630927493968080E-04 au^3/d^2 Small perturbers: Yes {source: SB441-N16} Output units : AU-D, deg, Julian Day Number (Tp) Calendar mode : Mixed Julian/Gregorian Output type : GEOMETRIC osculating elements Output format : 10 Reference frame : Ecliptic of J2000.0 ******************************************************************************* Initial IAU76/J2000 heliocentric ecliptic osculating elements (au, days, deg.): EPOCH= 2456413.5 ! 2013-May-01.0000000 (TDB) RMSW= n.a. EC= 1.00000509491957 QR= .01246672509220626 TP= 2456625.2645311668 OM= 295.6865414817095 W= 345.5411966905318 IN= 62.16289620932959 Equivalent ICRF heliocentric cartesian coordinates (au, au/d): X=-1.445349738222006E+00 Y= 3.101113524187381E+00 Z= 1.865345564350600E+00 VX= 4.232981685901609E-03 VY=-9.600824088002148E-03 VZ=-6.472975964240551E-03 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= n.a. M1= 10.4 M2= n.a. k1= 4.5 k2= n.a. PHCOF= n.a. Comet non-gravitational force model (AMRAT=m^2/kg;A1-A3=au/d^2;DT=days;R0=au): AMRAT= 0. DT= 0. A1= 8.537815093994E-8 A2= 5.695189237595E-9 A3= 0. Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 ******************************************************************************* JDTDB EC QR IN OM W Tp N MA TA A AD PR ******************************************************************************* $$SOE 2433282.500000000 = A.D. 1950-Jan-01 00:00:00.0000 TDB EC= 1.000000085260280E+00 QR= 1.238483072217976E-02 IN= 6.180337193417446E+01 OM= 2.957694292763332E+02 W = 3.455242655923076E+02 Tp= 2456625.165884805378 N = 1.781477238387309E-08 MA=-4.158442795706043E-04 TA= 1.813452866732768E+02 A =-1.452590897315034E+05 AD= 9.999999999999998E+99 PR= 9.999999999999998E+99 2469807.500000000 = A.D. 2050-Jan-01 00:00:00.0000 TDB EC= 1.000238358086915E+00 QR= 1.309438348862709E-02 IN= 6.216231318299613E+01 OM= 2.957263821583709E+02 W = 3.456344822227492E+02 Tp= 2456625.477025697008 N = 2.422213990842739E-03 MA= 3.192968047596763E+01 TA= 1.779765497565807E+02 A =-5.493576348989559E+01 AD= 9.999999999999998E+99 PR= 9.999999999999998E+99 $$EOE ******************************************************************************* TIME Barycentric Dynamical Time ("TDB" or T_eph) output was requested. This continuous coordinate time is equivalent to the relativistic proper time of a clock at rest in a reference frame co-moving with the solar system barycenter but outside the system's gravity well. It is the independent variable in the solar system relativistic equations of motion. TDB runs at a uniform rate of one SI second per second and is independent of irregularities in Earth's rotation. CALENDAR SYSTEM Mixed calendar mode was active such that calendar dates after AD 1582-Oct-15 (if any) are in the modern Gregorian system. Dates prior to 1582-Oct-5 (if any) are in the Julian calendar system, which is automatically extended for dates prior to its adoption on 45-Jan-1 BC. The Julian calendar is useful for matching historical dates. The Gregorian calendar more accurately corresponds to the Earth's orbital motion and seasons. A "Gregorian-only" calendar mode is available if such physical events are the primary interest. REFERENCE FRAME AND COORDINATES Ecliptic at the standard reference epoch Reference epoch: J2000.0 X-Y plane: adopted Earth orbital plane at the reference epoch Note: IAU76 obliquity of 84381.448 arcseconds wrt ICRF X-Y plane X-axis : ICRF Z-axis : perpendicular to the X-Y plane in the directional (+ or -) sense of Earth's north pole at the reference epoch. Symbol meaning [1 au= 149597870.700 km, 1 day= 86400.0 s]: JDTDB Julian Day Number, Barycentric Dynamical Time EC Eccentricity, e QR Periapsis distance, q (au) IN Inclination w.r.t X-Y plane, i (degrees) OM Longitude of Ascending Node, OMEGA, (degrees) W Argument of Perifocus, w (degrees) Tp Time of periapsis (Julian Day Number) N Mean motion, n (degrees/day) MA Mean anomaly, M (degrees) TA True anomaly, nu (degrees) A Semi-major axis, a (au) AD Apoapsis distance (au) PR Sidereal orbit period (day) ABERRATIONS AND CORRECTIONS Geometric osculating elements have NO corrections or aberrations applied. Computations by ... Solar System Dynamics Group, Horizons On-Line Ephemeris System 4800 Oak Grove Drive, Jet Propulsion Laboratory Pasadena, CA 91109 USA General site: https://ssd.jpl.nasa.gov/ Mailing list: https://ssd.jpl.nasa.gov/email_list.html System news : https://ssd.jpl.nasa.gov/horizons/news.html User Guide : https://ssd.jpl.nasa.gov/horizons/manual.html Connect : browser https://ssd.jpl.nasa.gov/horizons/app.html#/x API https://ssd-api.jpl.nasa.gov/doc/horizons.html command-line telnet ssd.jpl.nasa.gov 6775 e-mail/batch https://ssd.jpl.nasa.gov/ftp/ssd/horizons_batch.txt scripts https://ssd.jpl.nasa.gov/ftp/ssd/SCRIPTS Author : Jon.D.Giorgini@jpl.nasa.gov ******************************************************************************* !$$SOF CENTER = '@0' COMMAND = '2012 S1' OUT_UNITS = 'AU-D' START_TIME = '1950-01-01' STEP_SIZE = '100 years' STOP_TIME = '2050-01-01' TABLE_TYPE = 'ELEMENTS'