API VERSION: 1.2 API SOURCE: NASA/JPL Horizons API ******************************************************************************* Revised: Aug 14, 2024 Lucy Spacecraft / Sun -49 https://www.nasa.gov/mission_pages/lucy/main/index https://blogs.nasa.gov/lucy/ http://lucy.swri.edu/ Lucy launched 2021-Oct-16 @ 09:34 UTC from Cape Canaveral, Florida (SLC-41) on an Atlas V 401 launch vehicle. BACKGROUND: The 12-year mission will fly past seven different asteroid systems; two main belt objects and five Jupiter Trojans, two of which are known to have satellites (so at least nine objects in total). Flybys (UTC): 2022-Oct-16 Earth gravity assist #1 (@11:04:30.7 UTC, 6737.295 km from Earth center) 2023-Nov-01 152830 Dinkinesh (1999 VD57) target-of-opportunity added Jan 24, 2023 (@16:54:41.3 UTC, 700 m diameter; inner main belt; 450 km flyby) 2024-Dec-13 Earth gravity assist #2 (@ 04:15 UTC) 2025-Apr-20 52246 Donaldjohanson (4 km diameter; inner main belt; 960 km flyby @ 17:51 UTC) 2027-Aug-11 3548 Eurybates (64 km diameter; 1 km diameter satellite Queta; binary C-type Jupiter L4) 2027-Sep-15 15094 Polymele (21 km diameter; binary P-type; Jupiter L4) 2028-Apr-18 11351 Leucus (34 km diameter; D-type; slow rotator (466 hrs); Jupiter L4) 2028-Nov-11 21900 Orus (51 km diameter; D or C-type; possible binary; Jupiter L4) 2030-Dec-27 Earth gravity assist #3 2033-Mar-03 617 Patroclus (113 km diameter; 104 km satellite (Menoetius) at 680 km separation; Jupiter L5) 2033 End-of-mission. Lucy will continue to orbit the Sun, passing through the alternating Trojan swarms for hundreds of thousands, or perhaps millions, of years. SPACECRAFT PHYSICAL CHARACTERISTICS: Width : 14.25 m (46.75 ft) Height : 7.2 m (23.6 ft), or 3.8 m w/solar panels stored Depth : 2.78 m (9.12 ft) Solar Panel diameter: 7.3 m (23.9 ft) Dry Mass (unfueled) : 821 kg (1810 lbs) Wet Mass (fueled) : 1550 kg (3417 lbs) Power : 504 watts (at furthest encounter) SCIENCE INSTRUMENTS: L'Ralph - Color visible imager (the Multi-spectral Visible Imaging Camera, MVIC, 0.4-0.85 microns) and infrared imaging spectrometer (Linear Etalon Imaging Spectral Array, LEISA, 1-3.6 microns). L'LORRI - LOng Range Reconnaissance Imager; high spatial resolution visible imager. Panchromatic, covering the wavelengths 0.35-0.85 microns L'TES - Thermal Emission Spectrometer (6-75 microns). Similar to instruments flying on OSIRIS-REx and Mars Global Surveyor. High gain antenna - Mass determination via Doppler shift tracking. TRAJECTORY: Nominal asteroid trajectories consistent with flight-project planning are available for use as observing center (with '@' prefix ) or target (drop '@'): @ 20152830 (152830 Dinkinesh (1999 VD57)) @ 20052246 (52246 Donaldjohanson) @ 20000617 (617 Patroclus) @ 20011351 (11351 Leucus) @ 20015094 (15094 Polymele) @ 20021900 (21900 Orus) @ 920003548 (3548 Eurybates, body center) Maneuver plan: (m/s) TCM Name (DSM #) Date Delta-V Thrust Start Target Event/Object *TCM-02a 2-MAR-2022 1.252 17:00:00.000 DSM-1 *TCM-03 7-JUN-2022 4.205 17:00:00.000 Biased EGA-1 *TCM-04 21-JUN-2022 1.531 17:00:00.000 Biased EGA-1 *TCM-04a 3-AUG-2022 0.415 17:00:00.000 EGA-1 *TCM-08a 9-MAY-2023 3.441 17:00:00.000 target 1999 VD57 Encounter *TCM-08c 29-SEP-2023 0.061 17:00:00.000 target 1999 VD57 Encounter *DSM-2A/TCM-09A 31-JAN-2024 100.012 17:00:00.000 DSM-2B *DSM-2B/TCM-09B 3-FEB-2024 799.325 22:00:00.000 EGA2 biased *TCM-10 24-FEB-2024 17.189 17:00:00.000 EGA2 biased *TCM-10a 19-MAR-2024 0.838 16:00:00.000 EGA2 *TCM-10b 14-MAY-2024 0.247 17:00:00.000 EGA2 TCM-11 13-NOV-2024 0.078 17:00:00.000 EGA2 MEF-1 24-JAN-2025 1.933 17:00:00.000 Dj Encounter TCM-14 14-FEB-2025 0.039 17:00:00.000 Dj Encounter TCM-17 20-MAY-2025 0.132 17:00:00.000 DSM-3/TCM-18 MEF-2 2-MAR-2026 1.934 17:00:00.000 DSM-3/TCM-18 DSM-3/TCM-18 6-APR-2027 313.462 06:50:00.000 Eurybates Encounter TCM-22 19-AUG-2027 0.131 17:00:00.000 Polymele Encounter DSM-4/TCM-24 28-SEP-2027 122.294 19:30:00.000 Leucus Encounter DSM-5/TCM-29 26-JUL-2028 340.671 04:00:00.000 Orus Encounter TCM-33 11-DEC-2028 0.658 17:00:00.000 EGA3 TCM-37 25-JAN-2031 1.741 23:00:00.000 PM Encounter (* denotes completed event in this trajectory update) Post-launch trajectory from navigation (begins after booster separation). Data fit through 2024-Jul-29 (includes Dinkinesh reconstruction), prediction thereafter: NOTE: the reference trajectory through 2033 will be updated when revised instead of presenting more-frequent but short-term local OD reconstructions. Name Start (TDB) Stop (TDB) ------------------------------------------------ ----------------- ----------- 211016_330402_240718_OD070-R-TCM11-P-TCM37-P_v1 2021-Oct-16 10:34 2033-Apr-02 ******************************************************************************* ******************************************************************************* Ephemeris / API_USER Thu Dec 12 03:24:49 2024 Pasadena, USA / Horizons ******************************************************************************* Target body name: Lucy (spacecraft) (-49) {source: Lucy_merged_DE430} Center body name: Earth (399) {source: Lucy_merged_DE430} Center-site name: iTelescope Obs., Siding Spring ******************************************************************************* Start time : A.D. 2024-Nov-30 00:00:00.0000 UT Stop time : A.D. 2024-Dec-01 00:00:00.0000 UT Step-size : 10 minutes ******************************************************************************* Target pole/equ : undefined Target radii : undefined Center geodetic : 149.0644, -31.2733577, 1.16499 {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: 149.0644,5457.31536,-3292.4397 {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 : Earth Vis. interferer : MOON (R_eq= 1737.400) km {source: Lucy_merged_DE430} Rel. light bend : Sun {source: Lucy_merged_DE430} 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 RTS-only print : NO 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 ( 0.0deg=YES),Airmass (>38.000=NO), Daylight (YES) Table cut-offs 2: Solar elongation ( 12.0,180.0=YES),Local Hour Angle( 0.0=NO ) Table cut-offs 3: RA/DEC angular rate ( 0.0=NO ) *************************************************************************************************************************************************************************************************************************************************** Date__(UT)__HR:MN R.A._____(ICRF)_____DEC Azi____(a-app)___Elev APmag S-brt r rdot delta deldot S-O-T /r S-T-O T-O-M/MN_Illu% RA_3sigma DEC_3sigma Sky_motion Sky_mot_PA RelVel-ANG *************************************************************************************************************************************************************************************************************************************************** $$SOE >..... Daylight Cut-off Requested .....< 2024-Nov-30 09:00 C 18 39 47.52 -22 54 18.2 257.469061 25.204892 n.a. n.a. 0.918485713829 7.7260235 0.07996266531440 -10.6900689 30.8557 /T 146.5841 41.9/ 1.0117 n.a. n.a. 0.2307793 39.024905 -88.80460 2024-Nov-30 09:10 C 18 39 47.63 -22 54 16.4 256.385675 23.118016 n.a. n.a. 0.918516705016 7.7274775 0.07991979577620 -10.6854753 30.8491 /T 146.5926 41.8/ 0.9958 n.a. n.a. 0.2433994 41.855223 -88.73939 2024-Nov-30 09:20 C 18 39 47.76 -22 54 14.6 255.297491 21.040730 n.a. n.a. 0.918547702034 7.7289312 0.07987694330146 -10.6815622 30.8426 /T 146.6011 41.7/ 0.9799 n.a. n.a. 0.2564972 44.481925 -88.67180 2024-Nov-30 09:30 N 18 39 47.89 -22 54 12.7 254.201942 18.973841 n.a. n.a. 0.918578704882 7.7303847 0.07983410514655 -10.6783364 30.8361 /T 146.6096 41.6/ 0.9640 n.a. n.a. 0.2700132 46.922033 -88.60217 2024-Nov-30 09:40 N 18 39 48.04 -22 54 10.9 253.096561 16.918190 n.a. n.a. 0.918609713559 7.7318378 0.07979127854348 -10.6758033 30.8296 /T 146.6180 41.5/ 0.9480 n.a. n.a. 0.2838900 49.191936 -88.53080 2024-Nov-30 09:50 N 18 39 48.21 -22 54 09.0 251.978949 14.874657 n.a. n.a. 0.918640728063 7.7332907 0.07974846070506 -10.6739670 30.8232 /T 146.6263 41.4/ 0.9319 n.a. n.a. 0.2980728 51.307068 -88.45800 2024-Nov-30 10:00 A 18 39 48.38 -22 54 07.2 250.846752 12.844172 n.a. n.a. 0.918671748394 7.7347433 0.07970564883035 -10.6728303 30.8168 /T 146.6347 41.3/ 0.9159 n.a. n.a. 0.3125095 53.281741 -88.38405 2024-Nov-30 10:10 A 18 39 48.57 -22 54 05.3 249.697644 10.827715 n.a. n.a. 0.918702774550 7.7361956 0.07966284010992 -10.6723946 30.8105 /T 146.6429 41.2/ 0.8998 n.a. n.a. 0.3271497 55.129079 -88.30923 2024-Nov-30 10:20 A 18 39 48.77 -22 54 03.4 248.529308 8.826325 n.a. n.a. 0.918733806531 7.7376476 0.07962003173130 -10.6726600 30.8042 /T 146.6511 41.1/ 0.8837 n.a. n.a. 0.3419453 56.861024 -88.23380 2024-Nov-30 10:30 18 39 48.98 -22 54 01.6 247.339422 6.841107 n.a. n.a. 0.918764844335 7.7390993 0.07957722088430 -10.6736253 30.7980 /T 146.6593 41.0/ 0.8677 n.a. n.a. 0.3568501 58.488386 -88.15803 2024-Nov-30 10:40 18 39 49.21 -22 53 59.7 246.125646 4.873236 n.a. n.a. 0.918795887962 7.7405508 0.07953440476644 -10.6752878 30.7918 /T 146.6674 40.9/ 0.8516 n.a. n.a. 0.3718195 60.020916 -88.08214 2024-Nov-30 10:50 18 39 49.45 -22 53 57.9 244.885609 2.923964 n.a. n.a. 0.918826937409 7.7420019 0.07949158058825 -10.6776438 30.7857 /T 146.6754 40.8/ 0.8356 n.a. n.a. 0.3868105 61.467388 -88.00639 2024-Nov-30 11:00 18 39 49.70 -22 53 56.0 243.616904 0.994631 n.a. n.a. 0.918857992677 7.7434528 0.07944874557865 -10.6806878 30.7796 /T 146.6834 40.7/ 0.8196 n.a. n.a. 0.4017816 62.835691 -87.93101 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< $$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. SOLAR PRESENCE (OBSERVING SITE) Time tag is followed by a blank, then a solar-presence condition code: '*' Daylight (refracted solar upper-limb on or above apparent horizon) 'C' Civil twilight/dawn 'N' Nautical twilight/dawn 'A' Astronomical twilight/dawn ' ' Night OR geocentric ephemeris LUNAR PRESENCE WITH TARGET RISE/TRANSIT/SET EVENT MARKER (OBSERVING SITE) The solar-presence code column is immediately followed by another marker: 'm' Refracted upper-limb of Moon on or above apparent horizon ' ' Refracted upper-limb of Moon below apparent horizon OR geocentric The lunar presence marker (an ongoing state) can be over-ridden by a target event marker if an event has occurred since the last output step: 'r' Rise (target body on or went above cut-off RTS elevation) 'e' Elevation max (target body maximum elevation angle has occurred) 't' Transit (target body at or passed through observer meridian) 's' Set (target body on or went below cut-off RTS elevation) RTS MARKERS (TVH) Rise and set are with respect to the reference ellipsoid true visual horizon defined by the elevation cut-off angle. Horizon dip and yellow-light refraction (Earth only) are considered. Accuracy is < or = to twice the requested search step-size. '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} 'Azi____(a-app)___Elev' = Airless apparent azimuth and elevation of target center. Compensated for light-time, the gravitational deflection of light, stellar aberration, precession and nutation. Azimuth is measured clockwise from north: North(0) -> East(90) -> South(180) -> West(270) -> North (360) Elevation angle is with respect to a plane perpendicular to the reference surface local zenith direction. TOPOCENTRIC ONLY. Units: DEGREES 'APmag S-brt' = The targets' approximate apparent visual magnitude and surface brightness. For planets and natural satellites, output is restricted to solar phase angles covered by observational data. Outside the observed phase angle range, "n.a." may be output to avoid extrapolation beyond the limit of model validity. 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 '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 '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 'S-O-T /r' = Sun-Observer-Target apparent SOLAR ELONGATION ANGLE seen from the observers' location at print-time. The '/r' column provides a code indicating the targets' apparent position relative to the Sun in the observers' sky, as described below: Case A: For an observing location on the surface of a rotating body, that body rotational sense is considered: /T indicates target TRAILS Sun (evening sky: rises and sets AFTER Sun) /L indicates target LEADS Sun (morning sky: rises and sets BEFORE Sun) Case B: For an observing point that does not have a rotational model (such as a spacecraft), the "leading" and "trailing" condition is defined by the observers' heliocentric ORBITAL motion: * If continuing in the observers' current direction of heliocentric motion would encounter the targets' apparent longitude first, followed by the Sun's, the target LEADS the Sun as seen by the observer. * If the Sun's apparent longitude would be encountered first, followed by the targets', the target TRAILS the Sun. Two other codes can be output: /* indicates observer is Sun-centered (undefined) /? Target is aligned with Sun center (no lead or trail) The S-O-T solar elongation angle is numerically the minimum separation angle of the Sun and target in the sky in any direction. It does NOT indicate the amount of separation in the leading or trailing directions, which would be defined along the equator of a spherical coordinate system. Units: DEGREES 'S-T-O' = The Sun-Target-Observer angle; the interior vertex angle at target center formed by a vector from the target to the apparent center of the Sun (at reflection time on the target) and the apparent vector from target to the observer at print-time. Slightly different from true PHASE ANGLE (requestable separately) at the few arcsecond level in that it includes stellar aberration on the down-leg from target to observer. Units: DEGREES 'T-O-M/MN_Illu%' = Target-Observer-Moon LUNAR ELONGATION angle and illuminated percentage. The apparent lunar elongation angle between target body center and Moon center, seen from the observing site, along with fraction of the lunar disk illuminated by the Sun. A negative lunar elongation angle indicates the target center is behind the Moon. Units: DEGREES & PERCENT 'RA_3sigma DEC_3sigma' = Uncertainty in Right-Ascension and Declination. Output values are the formal +/- 3 standard-deviations (sigmas) around nominal position. Units: ARCSECONDS 'Sky_motion Sky_mot_PA RelVel-ANG' = Total apparent angular rate of the target in the plane-of-sky. "Sky_mot_PA" is the position angle of the target's direction of motion in the plane-of-sky, measured counter-clockwise from the apparent of-date north pole direction. "RelVel-ANG" is the flight path angle of the target's relative motion with respect to the observer's line-of-sight, in the range [-90,+90], where positive values indicate motion away from the observer, negative values are toward the observer: -90 = target is moving directly toward the observer 0 = target is moving at right angles to the observer's line-of-sight +90 = target is moving directly away from the observer UNITS: ARCSECONDS/MINUTE, DEGREES, DEGREES 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 ***************************************************************************************************************************************************************************************************************************************************