******************************************************************************* JPL/HORIZONS 21P/Giacobini-Zinner 2024-May-22 21:09:22 Rec #:90000322 (+COV) Soln.date: 2024-May-15_12:11:48 # obs: 1986 (2011-2024) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2458064.5 ! 2017-Nov-07.0000000 (TDB) RMSW= n.a. EC= .7104679234028084 QR= 1.013484087298204 TP= 2458371.7656382499 OM= 195.4051071228803 W= 172.8098023967457 IN= 32.00298706592557 A= 3.500420745119039 MA= 313.7578843129322 ADIST= 5.987357402939874 PER= 6.5492048652152 N= .150495565 ANGMOM= .022648914 DAN= 5.87401 DDN= 1.01681 L= 9.298686999999999 B= 3.8033409 MOID= .0179121 TP= 2018-Sep-10.2656382499 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= 1. M1= 13.3 M2= n.a. k1= 8. 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= 3.460712432861E-9 A2= -1.552008390427E-9 A3= -1.945282667875E-9 Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 COMET comments 1: soln ref.= JPL#K182/15, data arc: 2011-05-01 to 2024-05-08 2: k1=8.; ******************************************************************************* ******************************************************************************* Ephemeris / WWW_USER Wed May 22 21:09:22 2024 Pasadena, USA / Horizons ******************************************************************************* Target body name: 21P/Giacobini-Zinner {source: JPL#K182/15} Center body name: Earth (399) {source: DE441} Center-site name: GEOCENTRIC ******************************************************************************* Start time : A.D. 2025-Mar-22 00:00:00.0000 UT Stop time : A.D. 2025-Mar-28 00:00:00.0000 UT Step-size : 180 minutes ******************************************************************************* Target pole/equ : undefined Target radii : 1. km 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.240522.p240815 EOP coverage : DATA-BASED 1962-JAN-20 TO 2024-MAY-22. PREDICTS-> 2024-AUG-14 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= 2458064.5 ! 2017-Nov-07.0000000 (TDB) RMSW= n.a. EC= .7104679234028084 QR= 1.013484087298204 TP= 2458371.7656382499 OM= 195.4051071228803 W= 172.8098023967457 IN= 32.00298706592557 Equivalent ICRF heliocentric cartesian coordinates (au, au/d): X=-2.008849931392910E+00 Y=-2.699148209790900E+00 Z= 7.334033824844510E-02 VX= 9.365206292248416E-03 VY= 1.519885581555384E-03 VZ= 1.140010905389097E-03 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= 1. M1= 13.3 M2= n.a. k1= 8. 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= 3.460712432861E-9 A2= -1.552008390427E-9 A3= -1.945282667875E-9 Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 ******************************************************************************* Date__(UT)__HR:MN r rdot ************************************************** $$SOE 2025-Mar-22 00:00 1.010131260778 -1.2049318 2025-Mar-22 03:00 1.010045879213 -1.1604192 2025-Mar-22 06:00 1.009963711764 -1.1158904 2025-Mar-22 09:00 1.009884759583 -1.0713459 2025-Mar-22 12:00 1.009809023777 -1.0267864 2025-Mar-22 15:00 1.009736505409 -0.9822124 2025-Mar-22 18:00 1.009667205498 -0.9376247 2025-Mar-22 21:00 1.009601125016 -0.8930238 2025-Mar-23 00:00 1.009538264891 -0.8484103 2025-Mar-23 03:00 1.009478626006 -0.8037849 2025-Mar-23 06:00 1.009422209199 -0.7591482 2025-Mar-23 09:00 1.009369015263 -0.7145008 2025-Mar-23 12:00 1.009319044946 -0.6698434 2025-Mar-23 15:00 1.009272298950 -0.6251765 2025-Mar-23 18:00 1.009228777932 -0.5805008 2025-Mar-23 21:00 1.009188482505 -0.5358170 2025-Mar-24 00:00 1.009151413235 -0.4911256 2025-Mar-24 03:00 1.009117570642 -0.4464273 2025-Mar-24 06:00 1.009086955204 -0.4017228 2025-Mar-24 09:00 1.009059567351 -0.3570125 2025-Mar-24 12:00 1.009035407467 -0.3122973 2025-Mar-24 15:00 1.009014475892 -0.2675776 2025-Mar-24 18:00 1.008996772920 -0.2228542 2025-Mar-24 21:00 1.008982298801 -0.1781276 2025-Mar-25 00:00 1.008971053736 -0.1333985 2025-Mar-25 03:00 1.008963037884 -0.0886676 2025-Mar-25 06:00 1.008958251356 -0.0439354 2025-Mar-25 09:00 1.008956694220 0.0007974 2025-Mar-25 12:00 1.008958366495 0.0455302 2025-Mar-25 15:00 1.008963268158 0.0902624 2025-Mar-25 18:00 1.008971399139 0.1349933 2025-Mar-25 21:00 1.008982759321 0.1797222 2025-Mar-26 00:00 1.008997348543 0.2244486 2025-Mar-26 03:00 1.009015166600 0.2691719 2025-Mar-26 06:00 1.009036213238 0.3138913 2025-Mar-26 09:00 1.009060488159 0.3586064 2025-Mar-26 12:00 1.009087991021 0.4033163 2025-Mar-26 15:00 1.009118721436 0.4480206 2025-Mar-26 18:00 1.009152678968 0.4927186 2025-Mar-26 21:00 1.009189863138 0.5374096 2025-Mar-27 00:00 1.009230273422 0.5820930 2025-Mar-27 03:00 1.009273909249 0.6267682 2025-Mar-27 06:00 1.009320770004 0.6714346 2025-Mar-27 09:00 1.009370855026 0.7160915 2025-Mar-27 12:00 1.009424163608 0.7607384 2025-Mar-27 15:00 1.009480695000 0.8053745 2025-Mar-27 18:00 1.009540448405 0.8499993 2025-Mar-27 21:00 1.009603422982 0.8946122 2025-Mar-28 00:00 1.009669617843 0.9392125 $$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 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/hrzn_batch.txt scripts https://ssd.jpl.nasa.gov/ftp/ssd/SCRIPTS Author : Jon.D.Giorgini@jpl.nasa.gov ******************************************************************************* !$$SOF COMMAND = '90000322' QUANTITIES = '19' START_TIME = '2025-Mar-22' STEP_SIZE = '3 hours' STOP_TIME = '2025-Mar-28'