******************************************************************************* JPL/HORIZONS 78P/Gehrels 2 2025-Dec-12 17:50:17 Rec #:90000843 (+COV) Soln.date: 2019-May-15_15:45:35 # obs: 5079 (2004-2013) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2454704.5 ! 2008-Aug-26.0000000 (TDB) RMSW= n.a. EC= .4615777504879729 QR= 2.011175662016283 TP= 2455940.7652741587 OM= 210.5448033068782 W= 192.9048299362199 IN= 6.252653039083802 A= 3.735313063007731 MA= 191.2183476271049 ADIST= 5.459450463999179 PER= 7.2193602224983 N= .136525433 ANGMOM= .029492895 DAN= 5.34374 DDN= 2.02735 L= 43.3754143 B= -1.3937867 MOID= 1.01947999 TP= 2012-Jan-14.2652741587 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= n.a. M1= 9.1 M2= 12.5 k1= 13.25 k2= 5. PHCOF= .030 Comet non-gravitational force model (AMRAT=m^2/kg;A1-A3=au/d^2;DT=days;R0=au): AMRAT= 0. DT= 0. A1= 1.730199933052E-8 A2= -9.69542324543E-9 A3= -7.201610505581E-10 Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 COMET comments 1: soln ref.= JPL#K122/1, data arc: 2004-05-12 to 2013-04-17 2: k1=13.25, k2=5., phase coef.=0.03; ******************************************************************************* ******************************************************************************* Ephemeris / WWW_USER Fri Dec 12 17:50:17 2025 Pasadena, USA / Horizons ******************************************************************************* Target body name: 78P/Gehrels 2 {source: JPL#K122/1} Center body name: Earth (399) {source: DE441} Center-site name: GEOCENTRIC ******************************************************************************* Start time : A.D. 2024-May-26 00:00:00.0000 UT Stop time : A.D. 2024-May-27 00:00:00.0000 UT Step-size : 2880 minutes ******************************************************************************* Target pole/equ : undefined Target radii : undefined Center geodetic : 0.0, 0.0, -6378.137 {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: 0.0, 0.0, 0.0 {E-lon(deg),Dxy(km),Dz(km)} Center pole/equ : ITRF93 {East-longitude positive} Center radii : 6378.137, 6378.137, 6356.752 km {Equator_a, b, pole_c} Target primary : Sun Vis. interferer : MOON (R_eq= 1737.400) km {source: DE441} Rel. light bend : Sun {source: DE441} Rel. lght bnd GM: 1.3271E+11 km^3/s^2 Small-body perts: Yes {source: SB441-N16} Atmos refraction: NO (AIRLESS) RA format : HMS Time format : CAL Calendar mode : Mixed Julian/Gregorian EOP file : eop.251212.p260310 EOP coverage : DATA-BASED 1962-JAN-20 TO 2025-DEC-12. PREDICTS-> 2026-MAR-09 Units conversion: 1 au= 149597870.700 km, c= 299792.458 km/s, 1 day= 86400.0 s Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (NO ) Table cut-offs 2: Solar elongation ( 0.0,180.0=NO ),Local Hour Angle( 0.0=NO ) Table cut-offs 3: RA/DEC angular rate ( 0.0=NO ) ******************************************************************************* Initial IAU76/J2000 heliocentric ecliptic osculating elements (au, days, deg.): EPOCH= 2454704.5 ! 2008-Aug-26.0000000 (TDB) RMSW= n.a. EC= .4615777504879729 QR= 2.011175662016283 TP= 2455940.7652741587 OM= 210.5448033068782 W= 192.9048299362199 IN= 6.252653039083802 Equivalent ICRF heliocentric cartesian coordinates (au, au/d): X=-3.639423566978304E+00 Y=-3.782122458384864E+00 Z=-1.444643546694240E+00 VX= 4.269727135952394E-03 VY=-3.256015549731198E-03 VZ=-8.120639465359486E-04 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= n.a. M1= 9.1 M2= 12.5 k1= 13.25 k2= 5. PHCOF= .030 Comet non-gravitational force model (AMRAT=m^2/kg;A1-A3=au/d^2;DT=days;R0=au): AMRAT= 0. DT= 0. A1= 1.730199933052E-8 A2= -9.69542324543E-9 A3= -7.201610505581E-10 Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 ********************************************************************************************* Date__(UT)__HR:MN r rdot delta deldot S-O-T /r ********************************************************************************************* $$SOE 2024-May-26 00:00 4.733811613691 -4.5959769 3.75736201989741 -12.4769990 162.6152 /L $$EOE ********************************************************************************************* Column meaning: TIME Times PRIOR to 1962 are UT1, a mean-solar time closely related to the prior but now-deprecated GMT. Times AFTER 1962 are in UTC, the current civil or "wall-clock" time-scale. UTC is kept within 0.9 seconds of UT1 using integer leap-seconds for 1972 and later years. Conversion from the internal Barycentric Dynamical Time (TDB) of solar system dynamics to the non-uniform civil UT time-scale requested for output has not been determined for UTC times after the next July or January 1st. Therefore, the last known leap-second is used as a constant over future intervals. Time tags refer to the UT time-scale conversion from TDB on Earth regardless of observer location within the solar system, although clock rates may differ due to the local gravity field and no analog to "UT" may be defined for that location. Any 'b' symbol in the 1st-column denotes a B.C. date. First-column blank (" ") denotes an A.D. date. 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. NOTE: "n.a." in output means quantity "not available" at the print-time. 'r rdot' = The Sun's apparent range ("r", light-time aberrated) and range-rate ("rdot") relative to the target center, as seen by the observer. A positive "rdot" means the target center was moving away from the Sun, negative means moving toward the Sun. Units: AU and KM/S 'delta deldot' = Apparent range ("delta", light-time aberrated) and range-rate ("delta-dot") of the target center relative to the observer. A positive "deldot" means the target center is moving away from the observer, negative indicates movement toward the observer. Units: AU and KM/S 'S-O-T /r' = Sun-Observer-Target apparent SOLAR ELONGATION ANGLE seen from the observers' location at print-time. The '/r' column provides a code indicating the targets' apparent position relative to the Sun in the observers' sky, as described below: Case A: For an observing location on the surface of a rotating body, that body rotational sense is considered: /T indicates target TRAILS Sun (evening sky: rises and sets AFTER Sun) /L indicates target LEADS Sun (morning sky: rises and sets BEFORE Sun) Case B: For an observing point that does not have a rotational model (such as a spacecraft), the "leading" and "trailing" condition is defined by the observers' heliocentric ORBITAL motion: * If continuing in the observers' current direction of heliocentric motion would encounter the targets' apparent longitude first, followed by the Sun's, the target LEADS the Sun as seen by the observer. * If the Sun's apparent longitude would be encountered first, followed by the targets', the target TRAILS the Sun. Two other codes can be output: /* indicates observer is Sun-centered (undefined) /? Target is aligned with Sun center (no lead or trail) The S-O-T solar elongation angle is numerically the minimum separation angle of the Sun and target in the sky in any direction. It does NOT indicate the amount of separation in the leading or trailing directions, which would be defined along the equator of a spherical coordinate system. Units: DEGREES 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 COMMAND = '90000843' QUANTITIES = '19,20,23' START_TIME = '2024-May-26 STEP_SIZE = '2 days' STOP_TIME = '2024-May-27'