******************************************************************************* JPL/HORIZONS (2021 UA1) 2025-Dec-12 18:00:55 Rec #:50486930 (+COV) Soln.date: 2021-Oct-26_07:32:49 # obs: 22 (1 days) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2459513.5 ! 2021-Oct-26.00 (TDB) Residual RMS= .43799 EC= .405604751630822 QR= .6456521044150743 TP= 2459449.1708402317 OM= 126.6360051750638 W= 162.5411087953244 IN= .005944196205087182 A= 1.086233623479542 MA= 56.0050371919295 ADIST= 1.526815142544009 PER= 1.13212 N= .870601099 ANGMOM= .016387486 DAN= 1.48028 DDN= .65435 L= 289.1771141 B= .0017834 MOID= 7.349E-5 TP= 2021-Aug-22.6708402317 Asteroid physical parameters (km, seconds, rotational period in hours): GM= n.a. RAD= n.a. ROTPER= n.a. H= 31.84 G= .150 B-V= n.a. ALBEDO= n.a. STYP= n.a. ASTEROID comments: 1: soln ref.= JPL#3, OCC=6 2: source=ORB ******************************************************************************* ******************************************************************************* Ephemeris / WWW_USER Fri Dec 12 18:00:55 2025 Pasadena, USA / Horizons ******************************************************************************* Target body name: (2021 UA1) {source: JPL#3} Center body name: Earth (399) {source: DE441} Center-site name: GEOCENTRIC ******************************************************************************* Start time : A.D. 2021-Oct-25 03:05:00.0000 UT Stop time : A.D. 2021-Oct-25 03:09:00.0000 UT Step-size : 1 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= 2459513.5 ! 2021-Oct-26.00 (TDB) Residual RMS= .43799 EC= .405604751630822 QR= .6456521044150743 TP= 2459449.1708402317 OM= 126.6360051750638 W= 162.5411087953244 IN= .005944196205087182 Equivalent ICRF heliocentric cartesian coordinates (au, au/d): X= 8.444874431522708E-01 Y= 4.925738962629773E-01 Z= 2.134440702524450E-01 VX=-2.769488837858590E-03 VY= 1.618905073893188E-02 VZ= 7.017873193241940E-03 Asteroid physical parameters (km, seconds, rotational period in hours): GM= n.a. RAD= n.a. ROTPER= n.a. H= 31.84 G= .150 B-V= n.a. ALBEDO= n.a. STYP= n.a. ******************************************************************************************************************** Date__(UT)__HR:MN R.A._____(ICRF)_____DEC APmag S-brt delta deldot RNG_3sigma RNGRT_3sig ******************************************************************************************************************** $$SOE 2021-Oct-25 03:05 11 55 27.97 -81 53 48.1 14.941 n.a. 0.00006325402415 -1.2533700 10.1251 0.0326224 2021-Oct-25 03:06 09 13 27.62 -86 11 24.0 14.616 n.a. 0.00006301592473 0.0687606 9.7975 0.0328719 2021-Oct-25 03:07 04 14 47.30 -84 33 27.7 14.343 n.a. 0.00006330893364 1.3890485 16.4822 0.0325980 2021-Oct-25 03:08 02 53 24.84 -79 33 48.2 14.121 n.a. 0.00006412527781 2.6728480 24.7622 0.0318312 2021-Oct-25 03:09 02 26 19.94 -74 18 06.8 13.943 n.a. 0.00006544405941 3.8899957 32.9952 0.0306482 $$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. STATISTICAL UNCERTAINTIES Output includes formal +/- 3 standard-deviation statistical orbit uncertainty quantities. There is a 99.7% (1-D) or 98.9% (2-D) chance the actual value is within given bounds. These statistical calculations assume observational data errors are random. If there are systematic biases (such as timing, reduction or star-catalog errors), results can be optimistic. Because the epoch covariance is mapped using linearized variational partial derivatives, results can also be optimistic for times far from the solution epoch, particularly for objects having close planetary encounters. 'R.A._____(ICRF)_____DEC' = Astrometric right ascension and declination of the target center with respect to the observing site (coordinate origin) in the reference frame of the planetary ephemeris (ICRF). Compensated for down-leg light-time delay aberration. Units: RA in hours-minutes-seconds of time, HH MM SS.ff{ffff} DEC in degrees-minutes-seconds of arc, sDD MN SC.f{ffff} 'APmag S-brt' = The asteroids' approximate apparent airless visual magnitude and surface brightness using the standard IAU H-G system magnitude model: APmag = H + 5*log10(delta) + 5*log10(r) - 2.5*log10((1-G)*phi_1 + G*phi_2) For solar phase angles >90 deg, the error could exceed 1 magnitude. For phase angles >120 degrees, output values are rounded to the nearest integer to indicate error could be large and unknown. For Earth-based observers, the estimated dimming due to atmospheric absorption (extinction) is available as a separate, requestable quantity. Surface brightness is the average airless visual magnitude of a square-arcsecond of the illuminated portion of the apparent disk. It is computed only if the target radius is known. Units: MAGNITUDES & MAGNITUDES PER SQUARE ARCSECOND '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 'RNG_3sigma RNGRT_3sig' = Range and range rate (radial velocity) formal 3-standard-deviation uncertainties. Units: KM, 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 ******************************************************************************************************************** !$$SOF COMMAND = '2021 UA1' QUANTITIES = '1,9,20,39' START_TIME = '2021-10-25 03:05' STEP_SIZE = '1 minute' STOP_TIME = '2021-10-25 03:09'