API VERSION: 1.2 API SOURCE: NASA/JPL Horizons API ****************************************************************************** Revised: Nov 10, 2025 IMAP Spacecraft / (Earth) -43 https://imap.princeton.edu/ BACKGROUND: The "Interstellar Mapping and Acceleration Probe" (IMAP) will study the energization of charged particles and interaction of the solar wind with that of other stars and material in our galaxy. IMAP is the fifth mission in NASA's Solar Terrestrial Probes (STP) Program. It was launched Sep. 24, 2025 @ 11:30 UTC from Launch Complex 39A (LC-39A) at Kennedy Space Center, USA, on a Falcon 9 booster. From a halo-orbit at the Earth-Sun L1 Lagrange Point, ~1.6 million km closer to the Sun than Earth and free from planetary magnetic influences, IMAP will spin once every 15 seconds while using 10 instruments to scan the heliosphere. SCIENCE GOALS * What elements make up the interstellar gas and dust (indication of origin) * How does the solar wind and interstellar medium interact through the boundaries of our heliosphere? * What causes some solar particles to get accelerated to nearly the speed of light, making them dangerous to satellites and astronauts, and how can it be predicted when these particles will occur? SPACECRAFT PHYSICAL CHARACTERISTICS: Dry mass : ~800 kg Launch mass : ~900 kg Dimensions : cylindrical, 3-m diameter, 1.5-m height. 2.5-m boom Solar arrays : 500 Watts, sun-facing Spin : 4 rpm Communications : X-band, 375-500 kilobits/s down, 2 kbps up. Propulsion : 12 thrusters, three hydrazine tanks Launch vehicle : Space-X Falcon-9 from Kennedy Space Center SPACECRAFT TRAJECTORY: Post-launch merge, tracking data through Nov. 03, predicts thereafter. Trajectory name Start Stop -------------------------------------- ----------------- ----------------- imap_pred_od000_20250924_20251022_v01 2025-Sep-24 13:02 2025-Sep-24 13:30 imap_pred_od001_20250924_20251022_v03 2025-Sep-24 13:30 2025-Sep-26 12:00 imap_pred_od002_20250926_20251024_v01 2025-Sep-26 12:00 2025-Sep-29 12:00 imap_pred_od003_20250929_20251027_v01 2025-Sep-29 12:01 2025-Oct-02 12:00 imap_pred_od004_20251002_20251113_v01 2025-Oct-02 12:00 2025-Oct-16 12:45 imap_pred_od006_20251016_20251127_v01 2025-Oct-16 12:45 2025-Oct-21 00:01 imap_pred_od007_20251021_20251118_v01 2025-Oct-21 00:01 2025-Nov-04 00:01 imap_pred_od009_20251104_20251216_v01 2025-Nov-04 00:01 2025-Dec-15 23:59 ******************************************************************************* ******************************************************************************* Ephemeris / API_USER Sun Nov 16 07:59:59 2025 Pasadena, USA / Horizons ******************************************************************************* Target body name: IMAP (spacecraft) (-43) {source: IMAP_merged} Center body name: Earth (399) {source: DE441} Center-site name: El Berrueco ******************************************************************************* Start time : A.D. 2025-Oct-13 00:00:00.0000 UT Stop time : A.D. 2025-Oct-27 00:00:00.0000 UT Step-size : 10 minutes ******************************************************************************* Target pole/equ : undefined Target radii : undefined Center geodetic : 356.4134, 40.8833094, 1.06361 {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: 356.4134,4829.88693,4153.33056 {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: DE441} Rel. light bend : Sun {source: DE441} 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.251114.p260210 EOP coverage : DATA-BASED 1962-JAN-20 TO 2025-NOV-14. PREDICTS-> 2026-FEB-09 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 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Solar Elongation Cut-off Requested .....< 2025-Oct-22 05:30 Ar 13 06 41.27 -03 20 39.2 94.476014 -0.149614 n.a. n.a. 0.986450226977 -0.6093133 0.00905120346376 -0.1779618 12.5507 /L 167.3350 22.0/ 0.6931 n.a. n.a. 0.8457406 143.84901 -62.52860 2025-Oct-22 05:40 N 13 06 41.55 -03 20 46.0 96.120014 1.735365 n.a. n.a. 0.986447783382 -0.6092080 0.00905049151213 -0.1769561 12.5553 /L 167.3304 22.1/ 0.7048 n.a. n.a. 0.7709749 152.28020 -64.51617 2025-Oct-22 05:50 N 13 06 41.75 -03 20 52.8 97.772550 3.614822 n.a. n.a. 0.986445340209 -0.6091027 0.00904978493652 -0.1752813 12.5601 /L 167.3255 22.2/ 0.7166 n.a. n.a. 0.7159750 162.20107 -65.92371 2025-Oct-22 06:00 N 13 06 41.84 -03 20 59.7 99.437198 5.487146 n.a. n.a. 0.986442897459 -0.6089975 0.00904908641512 -0.1729404 12.5653 /L 167.3203 22.3/ 0.7284 n.a. n.a. 0.6852194 173.30348 -66.56860 2025-Oct-22 06:10 C 13 06 41.85 -03 21 06.5 101.117567 7.350681 n.a. n.a. 0.986440455130 -0.6088923 0.00904839861128 -0.1699376 12.5707 /L 167.3149 22.3/ 0.7401 n.a. n.a. 0.6814835 184.88028 -66.31713 2025-Oct-22 06:20 C 13 06 41.77 -03 21 13.2 102.817320 9.203710 n.a. n.a. 0.986438013223 -0.6087871 0.00904772416836 -0.1662787 12.5765 /L 167.3091 22.4/ 0.7518 n.a. n.a. 0.7044983 196.02806 -65.13831 >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Oct-23 05:30 Ar 13 07 44.50 -03 32 23.9 95.096245 0.266019 n.a. n.a. 0.986102652756 -0.5943827 0.00914718378844 -0.1895534 13.1820 /L 166.6968 33.1/ 3.0129 n.a. n.a. 0.8330121 146.28267 -64.08528 2025-Oct-23 05:40 N 13 07 44.76 -03 32 30.9 96.742027 2.149047 n.a. n.a. 0.986100269038 -0.5942806 0.00914642574443 -0.1883499 13.1866 /L 166.6921 33.2/ 3.0395 n.a. n.a. 0.7642673 154.94189 -65.83864 2025-Oct-23 05:50 N 13 07 44.93 -03 32 37.8 98.397401 4.025952 n.a. n.a. 0.986097885729 -0.5941785 0.00914567386835 -0.1864781 13.1916 /L 166.6871 33.3/ 3.0659 n.a. n.a. 0.7158661 164.97374 -67.00446 2025-Oct-23 06:00 N 13 07 45.01 -03 32 44.7 100.065946 5.895110 n.a. n.a. 0.986095502830 -0.5940764 0.00914493083401 -0.1839415 13.1969 /L 166.6818 33.4/ 3.0922 n.a. n.a. 0.6917478 175.99037 -67.42688 2025-Oct-23 06:10 C 13 07 45.00 -03 32 51.6 101.751277 7.754849 n.a. n.a. 0.986093120340 -0.5939743 0.00914419929890 -0.1807447 13.2025 /L 166.6762 33.5/ 3.1183 n.a. n.a. 0.6939003 187.26259 -67.00617 2025-Oct-23 06:20 C 13 07 44.89 -03 32 58.5 103.457063 9.603436 n.a. n.a. 0.986090738259 -0.5938723 0.00914348189904 -0.1768938 13.2084 /L 166.6702 33.6/ 3.1442 n.a. n.a. 0.7213704 197.95801 -65.73804 >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Oct-24 05:30 A 13 08 47.87 -03 44 10.4 95.716730 0.680261 n.a. n.a. 0.985763573400 -0.5798910 0.00923649651861 -0.2003488 13.8179 /L 166.0539 44.3/ 6.9689 n.a. n.a. 0.8213441 148.78988 -65.40651 2025-Oct-24 05:40 N 13 08 48.11 -03 44 17.4 97.364584 2.561115 n.a. n.a. 0.985761247798 -0.5797918 0.00923569557560 -0.1989477 13.8227 /L 166.0490 44.4/ 7.0104 n.a. n.a. 0.7587114 157.66072 -66.93863 2025-Oct-24 05:50 N 13 08 48.26 -03 44 24.4 99.023085 4.435243 n.a. n.a. 0.985758922594 -0.5796927 0.00923490159113 -0.1968793 13.8278 /L 166.0439 44.5/ 7.0517 n.a. n.a. 0.7169213 167.77324 -67.87905 2025-Oct-24 06:00 N 13 08 48.31 -03 44 31.4 100.695814 6.301007 n.a. n.a. 0.985756597788 -0.5795935 0.00923411723418 -0.1941475 13.8332 /L 166.0385 44.6/ 7.0926 n.a. n.a. 0.6993321 178.67101 -68.09697 2025-Oct-24 06:10 C 13 08 48.28 -03 44 38.4 102.386390 8.156719 n.a. n.a. 0.985754273379 -0.5794944 0.00923334515593 -0.1907572 13.8389 /L 166.0327 44.7/ 7.1334 n.a. n.a. 0.7071724 189.62123 -67.52217 2025-Oct-24 06:20 C 13 08 48.15 -03 44 45.3 104.098494 10.000625 n.a. n.a. 0.985751949368 -0.5793953 0.00923258798462 -0.1867149 13.8449 /L 166.0267 44.8/ 7.1738 n.a. n.a. 0.7388980 199.87043 -66.17139 2025-Oct-24 06:30 C 13 08 47.94 -03 44 52.3 105.835875 11.830889 n.a. n.a. 0.985749625754 -0.5792962 0.00923184832051 -0.1820282 13.8512 /L 166.0203 44.9/ 7.2138 n.a. n.a. 0.7907903 208.91758 -64.13588 >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Oct-25 05:30 A 13 09 51.30 -03 55 58.1 96.337684 1.093335 n.a. n.a. 0.985432744611 -0.5658063 0.00931957333176 -0.2103285 14.4582 /L 165.4065 55.6/ 12.4126 n.a. n.a. 0.8111076 151.36162 -66.51883 2025-Oct-25 05:40 N 13 09 51.51 -03 56 05.3 97.987900 2.971792 n.a. n.a. 0.985430475494 -0.5657098 0.00931873276063 -0.2087301 14.4631 /L 165.4016 55.7/ 12.4685 n.a. n.a. 0.7546592 160.41942 -67.84141 2025-Oct-25 05:50 N 13 09 51.64 -03 56 12.4 99.649817 4.842916 n.a. n.a. 0.985428206764 -0.5656134 0.00931789993726 -0.2064655 14.4683 /L 165.3963 55.8/ 12.5241 n.a. n.a. 0.7194472 170.57482 -68.57132 2025-Oct-25 06:00 N 13 09 51.67 -03 56 19.5 101.327015 6.705056 n.a. n.a. 0.985425938421 -0.5655169 0.00931707752536 -0.2035389 14.4738 /L 165.3908 55.9/ 12.5793 n.a. n.a. 0.7082174 181.31684 -68.60127 2025-Oct-25 06:10 C 13 09 51.62 -03 56 26.5 103.023124 8.556505 n.a. n.a. 0.985423670464 -0.5654205 0.00931626816934 -0.1999559 14.4796 /L 165.3849 56.0/ 12.6343 n.a. n.a. 0.7214831 191.92714 -67.88656 2025-Oct-25 06:20 C 13 09 51.47 -03 56 33.6 104.741828 10.395487 n.a. n.a. 0.985421402894 -0.5653241 0.00931547448921 -0.1957230 14.4858 /L 165.3787 56.1/ 12.6888 n.a. n.a. 0.7572078 201.73641 -66.46016 2025-Oct-25 06:30 C 13 09 51.24 -03 56 40.6 106.486892 12.220143 n.a. n.a. 0.985419135711 -0.5652278 0.00931469907556 -0.1908483 14.4922 /L 165.3723 56.2/ 12.7429 n.a. n.a. 0.8115779 210.34116 -64.41446 >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Oct-26 05:20 Ar 13 10 54.47 -04 07 40.0 95.315626 -0.376866 n.a. n.a. 0.985112154900 -0.5521917 0.00939773740495 -0.2206082 15.0978 /L 164.7598 66.8/ 19.1067 n.a. n.a. 0.8709793 145.98370 -65.84472 2025-Oct-26 05:30 A 13 10 54.75 -04 07 47.3 96.959295 1.505295 n.a. n.a. 0.985109940383 -0.5520977 0.00939685466126 -0.2194809 15.1025 /L 164.7551 66.9/ 19.1759 n.a. n.a. 0.8027261 153.97822 -67.44093 2025-Oct-26 05:40 N 13 10 54.94 -04 07 54.5 98.612163 3.381129 n.a. n.a. 0.985107726242 -0.5520038 0.00939597777944 -0.2176855 15.1075 /L 164.7500 67.0/ 19.2449 n.a. n.a. 0.7524858 163.18884 -68.56505 2025-Oct-26 05:50 N 13 10 55.04 -04 08 01.7 100.277782 5.249019 n.a. n.a. 0.985105512479 -0.5519098 0.00939510943309 -0.2152251 15.1128 /L 164.7447 67.1/ 19.3136 n.a. n.a. 0.7237437 173.34235 -69.09878 2025-Oct-26 06:00 N 13 10 55.05 -04 08 08.9 101.959737 7.107300 n.a. n.a. 0.985103299092 -0.5518159 0.00939425228019 -0.2121045 15.1185 /L 164.7390 67.2/ 19.3820 n.a. n.a. 0.7186176 183.88980 -68.95684 2025-Oct-26 06:10 N 13 10 54.97 -04 08 16.0 103.661662 8.954247 n.a. n.a. 0.985101086082 -0.5517220 0.00939340895796 -0.2083292 15.1244 /L 164.7330 67.3/ 19.4500 n.a. n.a. 0.7369684 194.14397 -68.11618 2025-Oct-26 06:20 C 13 10 54.81 -04 08 23.1 105.387252 10.788060 n.a. n.a. 0.985098873448 -0.5516281 0.00939258207771 -0.2039066 15.1306 /L 164.7267 67.4/ 19.5176 n.a. n.a. 0.7763701 203.52160 -66.62180 2025-Oct-26 06:30 C 13 10 54.56 -04 08 30.2 107.140279 12.606853 n.a. n.a. 0.985096661191 -0.5515343 0.00939177421992 -0.1988447 15.1372 /L 164.7202 67.5/ 19.5848 n.a. n.a. 0.8329845 211.70562 -64.56521 >..... Daylight Cut-off Requested .....< >..... Elevation 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/horizons_batch.txt scripts https://ssd.jpl.nasa.gov/ftp/ssd/SCRIPTS Author : Jon.D.Giorgini@jpl.nasa.gov ***************************************************************************************************************************************************************************************************************************************************