******************************************************************************* JPL/HORIZONS 1P/Halley 2024-Dec-12 02:26:32 Rec #:90000030 Soln.date: 2024-Apr-16_14:38:13 # obs: 8518 (1835-1994) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2439907.5 ! 1968-Feb-21.0000000 (TDB) RMSW= n.a. EC= .9679221169240834 QR= .575157544193894 TP= 2446469.6983372075 OM= 59.07198712310091 W= 112.2128395742619 IN= 162.1951462980701 A= 17.93003431157555 MA= 274.8113481508292 ADIST= 35.28491107895721 PER= 75.924140333742 N= .012981725 ANGMOM= .018301168 DAN= 1.78505 DDN= .82865 L= 305.8576622 B= 16.4442985 MOID= .0744805 TP= 1986-Feb-08.1983372075 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= 5.5 M1= 5.5 M2= 13.6 k1= 8. 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= 4.887227714062E-10 A2= 1.554720848799E-10 A3= 0. Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 COMET comments 1: soln ref.= JPL#74, data arc: 1835-08-21 to 1994-01-11 2: k1=8.0, k2=5.0, phase coef.=0.03; ******************************************************************************* ******************************************************************************* Ephemeris / WWW_USER Thu Dec 12 02:26:32 2024 Pasadena, USA / Horizons ******************************************************************************* Target body name: 1P/Halley {source: JPL#74} Center body name: Earth (399) {source: DE441} Center-site name: GEOCENTRIC ******************************************************************************* Start time : A.D. 2023-Dec-09 00:00:00.0000 UT Stop time : A.D. 2023-Dec-10 00:00:00.0000 UT Step-size : 60 minutes ******************************************************************************* Target pole/equ : undefined Target radii : 5.5 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.241211.p250309 EOP coverage : DATA-BASED 1962-JAN-20 TO 2024-DEC-11. PREDICTS-> 2025-MAR-08 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= 2439907.5 ! 1968-Feb-21.0000000 (TDB) RMSW= n.a. EC= .9679221169240834 QR= .575157544193894 TP= 2446469.6983372075 OM= 59.07198712310091 W= 112.2128395742619 IN= 162.1951462980701 Equivalent ICRF heliocentric cartesian coordinates (au, au/d): X=-1.326479811754316E+01 Y= 2.536681640257868E+01 Z= 2.638853433023532E+00 VX= 1.424523564115578E-03 VY=-1.432724119466060E-03 VZ= 4.019525745942034E-05 Comet physical (GM= km^3/s^2; RAD= km): GM= n.a. RAD= 5.5 M1= 5.5 M2= 13.6 k1= 8. 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= 4.887227714062E-10 A2= 1.554720848799E-10 A3= 0. Standard model: ALN= .1112620426 NK= 4.6142 NM= 2.15 NN= 5.093 R0= 2.808 ******************************************************************************* Date__(UT)__HR:MN r rdot VmagSn VmagOb *************************************************************************** $$SOE 2023-Dec-09 00:00 35.14346183837 0.0000172 0.9104520 30.8152580 2023-Dec-09 01:00 35.14346183858 0.0000003 0.9104511 30.8160176 2023-Dec-09 02:00 35.14346183838 -0.0000166 0.9104503 30.8167762 2023-Dec-09 03:00 35.14346183778 -0.0000335 0.9104494 30.8175337 2023-Dec-09 04:00 35.14346183676 -0.0000505 0.9104485 30.8182901 2023-Dec-09 05:00 35.14346183535 -0.0000674 0.9104476 30.8190454 2023-Dec-09 06:00 35.14346183352 -0.0000843 0.9104467 30.8197997 2023-Dec-09 07:00 35.14346183129 -0.0001012 0.9104459 30.8205529 2023-Dec-09 08:00 35.14346182865 -0.0001181 0.9104450 30.8213051 2023-Dec-09 09:00 35.14346182561 -0.0001350 0.9104441 30.8220561 2023-Dec-09 10:00 35.14346182216 -0.0001519 0.9104432 30.8228060 2023-Dec-09 11:00 35.14346181830 -0.0001688 0.9104423 30.8235548 2023-Dec-09 12:00 35.14346181403 -0.0001857 0.9104415 30.8243025 2023-Dec-09 13:00 35.14346180936 -0.0002026 0.9104406 30.8250490 2023-Dec-09 14:00 35.14346180428 -0.0002195 0.9104397 30.8257945 2023-Dec-09 15:00 35.14346179879 -0.0002364 0.9104388 30.8265387 2023-Dec-09 16:00 35.14346179290 -0.0002533 0.9104380 30.8272819 2023-Dec-09 17:00 35.14346178660 -0.0002703 0.9104371 30.8280238 2023-Dec-09 18:00 35.14346177989 -0.0002872 0.9104362 30.8287646 2023-Dec-09 19:00 35.14346177277 -0.0003041 0.9104353 30.8295043 2023-Dec-09 20:00 35.14346176525 -0.0003210 0.9104345 30.8302427 2023-Dec-09 21:00 35.14346175732 -0.0003379 0.9104336 30.8309800 2023-Dec-09 22:00 35.14346174899 -0.0003548 0.9104327 30.8317161 2023-Dec-09 23:00 35.14346174025 -0.0003717 0.9104318 30.8324509 2023-Dec-10 00:00 35.14346173110 -0.0003886 0.9104310 30.8331846 $$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 'VmagSn VmagOb' = Magnitude of target centers' velocity with respect to the Sun ("VmagSn") and the observer ("VmagOb") at the time light left the target center to be observed (print time minus down-leg light-time). These are absolute values of the velocity vectors (total speeds) and do NOT indicate direction of motion. Units: 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 = '90000030' START_TIME = '2023-Dec-09' STOP_TIME = '2023-Dec-10' STEP_SIZE = '1 hours' QUANTITIES = '19,22'