API VERSION: 1.2 API SOURCE: NASA/JPL Horizons API ******************************************************************************* JPL/HORIZONS 19521 Chaos (1998 WH24) 2025-Dec-12 18:18:55 Rec #: 19521 (+COV) Soln.date: 2025-Jul-02_16:01:32 # obs: 165 (1991-2023) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2459415.5 ! 2021-Jul-20.00 (TDB) Residual RMS= .091116 EC= .1001135120897042 QR= 41.02359324194614 TP= 2464043.0014227787 OM= 49.95094061309322 W= 56.43816270598113 IN= 12.03145500550502 A= 45.58751997400313 MA= 345.1822697310436 ADIST= 50.15144670606012 PER= 307.80605 N= .003202102 ANGMOM= .11556253 DAN= 42.76379 DDN= 47.77477 L= 105.8003409 B= 10.0029049 MOID= 40.05659866 TP= 2034-Mar-21.5014227787 Asteroid physical parameters (km, seconds, rotational period in hours): GM= n.a. RAD= n.a. ROTPER= n.a. H= 4.63 G= .150 B-V= n.a. ALBEDO= n.a. STYP= n.a. ASTEROID comments: 1: soln ref.= JPL#18, OCC=2 2: source=ORB ******************************************************************************* ******************************************************************************* Ephemeris / API_USER Fri Dec 12 18:18:56 2025 Pasadena, USA / Horizons ******************************************************************************* Target body name: 19521 Chaos (1998 WH24) {source: JPL#18} Center body name: Earth (399) {source: DE441} Center-site name: GEOCENTRIC ******************************************************************************* Start time : A.D. 2033-Dec-20 00:00:00.0000 UT Stop time : A.D. 2033-Dec-31 00:00:00.0000 UT Step-size : 180 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= 2459415.5 ! 2021-Jul-20.00 (TDB) Residual RMS= .091116 EC= .1001135120897042 QR= 41.02359324194614 TP= 2464043.0014227787 OM= 49.95094061309322 W= 56.43816270598113 IN= 12.03145500550502 Equivalent ICRF heliocentric cartesian coordinates (au, au/d): X= 1.696396148774111E+00 Y= 3.534344947057106E+01 Z= 2.112449260072316E+01 VX=-2.769170656890302E-03 VY=-2.004357501616938E-04 VZ= 4.019348565178183E-04 Asteroid physical parameters (km, seconds, rotational period in hours): GM= n.a. RAD= n.a. ROTPER= n.a. H= 4.63 G= .150 B-V= n.a. ALBEDO= n.a. STYP= n.a. ******************************************************************************* Date__(UT)__HR:MN r rdot ************************************************** $$SOE 2033-Dec-20 00:00 41.00239414370 -0.0001211 2033-Dec-20 03:00 41.00239413514 -0.0001160 2033-Dec-20 06:00 41.00239412695 -0.0001109 2033-Dec-20 09:00 41.00239411913 -0.0001058 2033-Dec-20 12:00 41.00239411167 -0.0001007 2033-Dec-20 15:00 41.00239410458 -0.0000956 2033-Dec-20 18:00 41.00239409786 -0.0000905 2033-Dec-20 21:00 41.00239409151 -0.0000854 2033-Dec-21 00:00 41.00239408553 -0.0000803 2033-Dec-21 03:00 41.00239407991 -0.0000752 2033-Dec-21 06:00 41.00239407466 -0.0000701 2033-Dec-21 09:00 41.00239406978 -0.0000650 2033-Dec-21 12:00 41.00239406527 -0.0000600 2033-Dec-21 15:00 41.00239406113 -0.0000549 2033-Dec-21 18:00 41.00239405735 -0.0000498 2033-Dec-21 21:00 41.00239405394 -0.0000447 2033-Dec-22 00:00 41.00239405090 -0.0000396 2033-Dec-22 03:00 41.00239404823 -0.0000345 2033-Dec-22 06:00 41.00239404592 -0.0000294 2033-Dec-22 09:00 41.00239404399 -0.0000243 2033-Dec-22 12:00 41.00239404242 -0.0000192 2033-Dec-22 15:00 41.00239404122 -0.0000141 2033-Dec-22 18:00 41.00239404039 -0.0000090 2033-Dec-22 21:00 41.00239403992 -0.0000039 2033-Dec-23 00:00 41.00239403982 0.0000012 2033-Dec-23 03:00 41.00239404009 0.0000063 2033-Dec-23 06:00 41.00239404073 0.0000114 2033-Dec-23 09:00 41.00239404174 0.0000165 2033-Dec-23 12:00 41.00239404312 0.0000216 2033-Dec-23 15:00 41.00239404486 0.0000267 2033-Dec-23 18:00 41.00239404697 0.0000318 2033-Dec-23 21:00 41.00239404945 0.0000369 2033-Dec-24 00:00 41.00239405229 0.0000420 2033-Dec-24 03:00 41.00239405551 0.0000471 2033-Dec-24 06:00 41.00239405909 0.0000522 2033-Dec-24 09:00 41.00239406304 0.0000573 2033-Dec-24 12:00 41.00239406736 0.0000624 2033-Dec-24 15:00 41.00239407205 0.0000675 2033-Dec-24 18:00 41.00239407710 0.0000726 2033-Dec-24 21:00 41.00239408253 0.0000777 2033-Dec-25 00:00 41.00239408832 0.0000828 2033-Dec-25 03:00 41.00239409447 0.0000879 2033-Dec-25 06:00 41.00239410100 0.0000929 2033-Dec-25 09:00 41.00239410789 0.0000980 2033-Dec-25 12:00 41.00239411516 0.0001031 2033-Dec-25 15:00 41.00239412279 0.0001082 2033-Dec-25 18:00 41.00239413079 0.0001133 2033-Dec-25 21:00 41.00239413915 0.0001184 2033-Dec-26 00:00 41.00239414789 0.0001235 2033-Dec-26 03:00 41.00239415699 0.0001286 2033-Dec-26 06:00 41.00239416646 0.0001337 2033-Dec-26 09:00 41.00239417630 0.0001388 2033-Dec-26 12:00 41.00239418650 0.0001439 2033-Dec-26 15:00 41.00239419707 0.0001490 2033-Dec-26 18:00 41.00239420802 0.0001541 2033-Dec-26 21:00 41.00239421933 0.0001592 2033-Dec-27 00:00 41.00239423100 0.0001643 2033-Dec-27 03:00 41.00239424305 0.0001694 2033-Dec-27 06:00 41.00239425546 0.0001745 2033-Dec-27 09:00 41.00239426824 0.0001796 2033-Dec-27 12:00 41.00239428139 0.0001847 2033-Dec-27 15:00 41.00239429491 0.0001898 2033-Dec-27 18:00 41.00239430879 0.0001949 2033-Dec-27 21:00 41.00239432305 0.0002000 2033-Dec-28 00:00 41.00239433767 0.0002051 2033-Dec-28 03:00 41.00239435266 0.0002102 2033-Dec-28 06:00 41.00239436801 0.0002153 2033-Dec-28 09:00 41.00239438374 0.0002203 2033-Dec-28 12:00 41.00239439983 0.0002254 2033-Dec-28 15:00 41.00239441629 0.0002305 2033-Dec-28 18:00 41.00239443312 0.0002356 2033-Dec-28 21:00 41.00239445031 0.0002407 2033-Dec-29 00:00 41.00239446787 0.0002458 2033-Dec-29 03:00 41.00239448581 0.0002509 2033-Dec-29 06:00 41.00239450410 0.0002560 2033-Dec-29 09:00 41.00239452277 0.0002611 2033-Dec-29 12:00 41.00239454180 0.0002662 2033-Dec-29 15:00 41.00239456121 0.0002713 2033-Dec-29 18:00 41.00239458098 0.0002764 2033-Dec-29 21:00 41.00239460111 0.0002815 2033-Dec-30 00:00 41.00239462162 0.0002866 2033-Dec-30 03:00 41.00239464249 0.0002917 2033-Dec-30 06:00 41.00239466373 0.0002968 2033-Dec-30 09:00 41.00239468534 0.0003019 2033-Dec-30 12:00 41.00239470732 0.0003069 2033-Dec-30 15:00 41.00239472966 0.0003120 2033-Dec-30 18:00 41.00239475237 0.0003171 2033-Dec-30 21:00 41.00239477545 0.0003222 2033-Dec-31 00:00 41.00239479890 0.0003273 $$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/horizons_batch.txt scripts https://ssd.jpl.nasa.gov/ftp/ssd/SCRIPTS Author : Jon.D.Giorgini@jpl.nasa.gov *******************************************************************************