******************************************************************************* Revised: Aug 11, 2021 101955 Bennu (1999 RQ36) 2101955 *SPECIAL* Soln.date: 2021-Jan-07_11:18:06 # obs: 554 (1999-2020) IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs): EPOCH= 2455562.5 ! 2011-Jan-01.00 (TDB) Residual RMS= .23164 EC= .2037450762416414 QR= .8968944004459729 TP= 2455439.14194087 OM= 2.060866195696420 W= 66.22306084084298 IN= 6.0349437702479403 A= 1.1263910258948120 MA= 101.7039520024729 ADIST= 1.355887651343651 PER= 1.19548 N= 0.824461327 ANGMOM= .017873901 DAN= 0.99768 DDN= 1.17626 L= 68.16622425 B= 5.521044 MOID= .0032228 TP= 2010-Aug-30.6419408992 Asteroid physical parameters (km, seconds, rotational period in hours): GM= n.a. RAD= .241 ROTPER= 4.2960610 H= 20.21 G= -0.031 B-V= 0.64 ALBEDO= .044 STYP= B Asteroid non-gravitational force model (AMRAT= m^2/kg;A1,A2,A3=au/d^2;R0=au): AMRAT= .00000026 A1= 0. A2= 0. A3= 0. Yarkovsky acceleration: RHO= 1191.5349121 This pre-computed trajectory of asteroid (101955) Bennu, covering 1900 to 2136 is based on ground-based optical and radar astrometry as well as pseudo-range measurements from the OSIRIS-REx mission. The trajectory accounts for the gravity of the Sun, the planets, Pluto, the Moon and 343 small-body perturbers, relativistic effect, the Yarkovsky effect, and other solar radiation perturbations. Full details are provided in Farnocchia et al. (2021): https://doi.org/10.1016/j.icarus.2021.114594 It may be used to generate ephemerides relative to the SPACECRAFT-BASED Bennu solution by specifying coordinate center as "@2101955", or extended physical ephemerides of Bennu such as sub-observer/solar latitude and longitude. Trajectory name Start (TDB) Stop (TDB) ---------------------------------------------- ----------- ----------- sb-101955-118_long 1900-Jan-01 2135-Oct-01 Due to the non-standard dynamical models enabled by extensive high-precision spacecraft data, Horizons won't generate new SPK files for Bennu. However, the final reconstructed mission SPK can be downloaded for use here: https://ssd.jpl.nasa.gov/ftp/xfr/sb-101955-118_long.bsp ASTEROID comments: 1: soln ref.= JPL#118, PHA OCC=0 radar(58 delay, 7 Dop.) 2: source=ORB; See Farnocchia et al. 2021 ******************************************************************************* ******************************************************************************* Ephemeris / WWW_USER Sun May 5 17:25:32 2024 Pasadena, USA / Horizons ******************************************************************************* Target body name: 101955 Bennu (1999 RQ36) (2101955) {source: ORX_merged_DE424} Center body name: Earth (399) {source: ORX_merged_DE424} Center-site name: GEOCENTRIC ******************************************************************************* Start time : A.D. 2045-Nov-25 00:00:00.0000 UT Stop time : A.D. 2045-Nov-29 00:00:00.0000 UT Step-size : 1440 minutes ******************************************************************************* Target pole/equ : IAU_BENNU {East-longitude positive} Target radii : .2831, .2712, .2497 km {Equator_a, b, pole_c} 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: ORX_merged_DE424} Rel. light bend : Sun {source: ORX_merged_DE424} Rel. lght bnd GM: 1.3271E+11 km^3/s^2 Atmos refraction: NO (AIRLESS) RA format : HMS Time format : CAL Calendar mode : Mixed Julian/Gregorian EOP file : eop.240503.p240727 EOP coverage : DATA-BASED 1962-JAN-20 TO 2024-MAY-03. PREDICTS-> 2024-JUL-26 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 ) ******************************************************************************* Date__(UT)__HR:MN delta deldot *************************************************** $$SOE 2045-Nov-25 00:00 2.34004927608182 0.2648037 2045-Nov-26 00:00 2.34017102881516 0.1567821 2045-Nov-27 00:00 2.34023032295960 0.0484931 2045-Nov-28 00:00 2.34022696684966 -0.0601909 2045-Nov-29 00:00 2.34016069892948 -0.1693818 $$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. '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 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 = 'Bennu' START_TIME = '2045-11-25' STOP_TIME = '2045-11-29' STEP_SIZE = '1 day' QUANTITIES = '20'