API VERSION: 1.2 API SOURCE: NASA/JPL Horizons API ******************************************************************************* Revised: Jul 19, 2026 Hubble Space Telescope -48 http://hubblesite.org BACKGROUND: Launched: April 24, 1990 [from space shuttle Discovery (STS-31)] Deployed: April 25, 1990 NOTE: HST ephemeris data can be unreliable during times of the following space shuttle servicing missions Servicing Mission 1 : 1993 (December 02-14) Servicing Mission 2 : 1997 (February 11-21) Servicing Mission 3A: 1999 (December 19-28) Servicing Mission 3B: 2002 (March 01-12) Servicing Mission 4 : 2009 (May 11-25) HUBBLE SPACE TELESCOPE: Length : 43.5 ft (13.2 m) Weight : 24,500 lb (11,110 kg) Maximum Diameter: 14 ft (4.2 m) Data return : ~120 Gigabytes (GB)/week Generic orbit facts: Altitude : 569 km, or 353 miles Inclination : 28.5 deg. to equator Orbit period : 97 minutes Orbital speed: 28,000 kph (17500 mph) SPACECRAFT TRAJECTORY: The trajectory here is a concatenation of publicly released JSpOC two-line elements. These can usually only be propagated reliably "days" into the future, and are updated frequently to maintain accuracy. ******************************************************************************* ******************************************************************************* Ephemeris / API_USER Sun Jul 19 09:21:29 2026 Pasadena, USA / Horizons ******************************************************************************* Target body name: Hubble Space Telescope (spacecraft) (-48) {source: hst} Center body name: Earth (399) {source: DE441} Center-site name: iTelescope Obs.,Beryl Junc. (Sato) ******************************************************************************* Start time : A.D. 2025-Jul-06 00:00:00.0000 UT Stop time : A.D. 2025-Jul-20 00:00:00.0000 UT Step-size : 10 minutes ******************************************************************************* Target pole/equ : undefined Target radii : undefined Center geodetic : 246.3025, 37.7377919, 1.56349 {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: 246.3025,5051.53114,3883.42609 {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.260717.p261013 EOP coverage : DATA-BASED 1962-JAN-20 TO 2026-JUL-17. PREDICTS-> 2026-OCT-12 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 .....< 2025-Jul-06 10:10 01 35 19.01 -25 33 51.0 127.777284 4.987004 n.a. n.a. 1.016644537380 -6.4345678 0.00001365906579 3.4635601 92.5991 /L 87.4008 125.0/ 81.3255 n.a. n.a. 38838.793 59.754219 28.374648 >..... Elevation Cut-off Requested .....< 2025-Jul-06 11:50 Ct 03 21 25.88 -20 00 59.3 122.942802 7.994997 n.a. n.a. 1.016628425179 -6.9066738 0.00001205708077 4.9565703 68.7110 /L 111.2889 136.3/ 81.8739 n.a. n.a. 36489.463 69.480319 42.983371 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-07 09:40 t 21 54 38.25 -43 10 25.4 171.056343 8.461946 n.a. n.a. 1.016642627464 -5.1280039 0.00001179127262 -1.2219994 139.6048 /L 40.3956 70.0/ 88.0015 n.a. n.a. 50335.357 76.207927 -9.661833 >..... Elevation Cut-off Requested .....< 2025-Jul-07 11:20 Nt 23 08 28.47 -34 12 08.1 175.220937 18.020570 n.a. n.a. 1.016628393682 -6.3484436 0.00000830101539 -0.3312454 126.2225 /L 53.7779 86.1/ 88.4137 n.a. n.a. 72284.872 84.072629 -2.611917 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< >..... Elevation Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-08 09:10 r 18 05 02.76 -43 39 13.0 206.872929 1.397329 n.a. n.a. 1.016633696453 -3.3389565 0.00001591051311 -4.7381305 154.9290 /T 25.0698 19.9/ 93.4307 n.a. n.a. 28758.142 98.944135 -40.58248 >..... Elevation Cut-off Requested .....< 2025-Jul-08 10:50 Ar 18 49 26.73 -29 04 54.6 224.458378 7.003695 n.a. n.a. 1.016622661485 -5.1351517 0.00001253384190 -5.1869891 171.8955 /T 8.1039 23.2/ 93.7121 n.a. n.a. 33608.120 103.06671 -45.52755 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< >..... Elevation Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-09 08:50 t 00 32 35.91 -23 58 09.3 125.712521 5.226253 n.a. n.a. 1.016604556554 -4.7718384 0.00001350953605 3.7870645 107.8253 /L 72.1750 85.9/ 97.3535 n.a. n.a. 38123.334 60.689353 31.313930 >..... Elevation Cut-off Requested .....< 2025-Jul-09 10:30 At 02 17 19.01 -19 42 29.8 121.978237 7.509043 n.a. n.a. 1.016590807459 -5.8953078 0.00001228927231 5.1418267 83.7739 /L 96.2263 107.6/ 97.5195 n.a. n.a. 34596.868 70.678517 45.013138 >..... Elevation Cut-off Requested .....< 2025-Jul-09 12:10 Ct 03 36 31.25 -26 57 45.6 130.593674 5.630621 n.a. n.a. 1.016575450784 -6.1911819 0.00001329236022 5.4549381 72.1540 /L 107.8460 114.1/ 97.7115 n.a. n.a. 29900.713 76.745288 48.627472 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-10 06:40 r 19 56 35.76 -50 00 58.0 164.288932 -0.392340 n.a. n.a. 1.016594558817 -0.9324181 0.00001718912700 -1.4306979 151.1829 /L 28.8164 24.9/ 99.4131 n.a. n.a. 34442.482 66.279478 -11.30001 >..... Elevation Cut-off Requested .....< 2025-Jul-10 08:20 t 20 52 33.91 -41 38 20.0 169.600225 9.733835 n.a. n.a. 1.016588266421 -3.0281522 0.00001119283389 -0.9193859 152.2523 /L 27.7481 27.7/ 99.4685 n.a. n.a. 53349.100 75.901359 -7.253589 >..... Elevation Cut-off Requested .....< 2025-Jul-10 10:00 t 22 12 30.37 -33 13 54.7 172.386654 18.706551 n.a. n.a. 1.016577664866 -4.6931844 0.00000810758895 0.1366832 140.1982 /L 39.8025 42.2/ 99.5288 n.a. n.a. 74071.360 83.446283 1.0828760 >..... Elevation Cut-off Requested .....< 2025-Jul-10 11:40 Nt 23 42 41.10 -34 03 59.1 174.715706 18.120324 n.a. n.a. 1.016564017886 -5.6979433 0.00000827014006 1.2938903 121.5437 /L 58.4568 59.9/ 99.5949 n.a. n.a. 71460.740 90.541011 10.268130 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-11 07:50 r 16 55 57.46 -42 11 20.9 207.696358 2.563895 n.a. n.a. 1.016564652577 -1.0395565 0.00001511116765 -4.7142175 143.5667 /T 36.4315 38.7/ 99.5852 n.a. n.a. 30378.014 99.201505 -40.34766 >..... Elevation Cut-off Requested .....< 2025-Jul-11 09:30 r 17 43 27.62 -28 03 18.2 224.674799 8.099886 n.a. n.a. 1.016558030854 -3.0165213 0.00001196865174 -5.0918408 156.9027 /T 23.0958 28.5/ 99.5492 n.a. n.a. 35844.555 103.42655 -44.47348 >..... Elevation Cut-off Requested .....< 2025-Jul-11 11:10 Ar 19 04 46.87 -21 49 29.5 232.132971 10.052338 n.a. n.a. 1.016547375230 -4.5675050 0.00001107807936 -4.6466926 175.8842 /T 4.1147 11.9/ 99.5065 n.a. n.a. 41732.835 109.89976 -39.73991 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-12 05:50 r 21 45 45.32 -31 35 32.3 130.757318 -0.544371 n.a. n.a. 1.016535999689 -0.6259099 0.00001732800013 2.2910391 147.4474 /L 32.5531 16.8/ 97.6977 n.a. n.a. 33150.687 53.788068 18.264603 >..... Elevation Cut-off Requested .....< 2025-Jul-12 07:30 t 23 32 06.46 -22 11 32.5 123.148084 5.180688 n.a. n.a. 1.016530173569 -2.5690917 0.00001352561539 4.1459675 123.4017 /L 56.5990 38.7/ 97.5550 n.a. n.a. 36646.741 61.777315 34.684173 >..... Elevation Cut-off Requested .....< 2025-Jul-12 09:10 t 01 14 42.80 -19 26 55.8 120.809016 6.715482 n.a. n.a. 1.016520319244 -4.1514344 0.00001268818256 5.3354224 99.6993 /L 80.3012 62.2/ 97.4208 n.a. n.a. 32204.435 71.958227 47.208296 >..... Elevation Cut-off Requested .....< 2025-Jul-12 10:50 At 02 30 06.59 -28 05 22.3 131.001304 4.515542 n.a. n.a. 1.016507520664 -5.1560047 0.00001392497613 5.5269201 87.2418 /L 92.7584 76.0/ 97.2795 n.a. n.a. 28072.215 77.138961 49.471030 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-13 05:20 t 18 53 12.62 -48 24 47.0 162.981942 0.798612 n.a. n.a. 1.016501112501 1.3186166 0.00001630899912 -1.1891922 152.4454 /T 27.5533 44.3/ 93.6460 n.a. n.a. 36517.421 66.124905 -9.374792 >..... Elevation Cut-off Requested .....< 2025-Jul-13 07:00 t 19 56 02.58 -39 49 47.5 166.972276 10.995175 n.a. n.a. 1.016499518027 -0.6286474 0.00001064403085 -0.4806706 161.1576 /L 18.8423 30.9/ 93.3707 n.a. n.a. 56418.351 75.014014 -3.782811 >..... Elevation Cut-off Requested .....< 2025-Jul-13 08:40 t 21 22 31.72 -32 13 40.1 168.161356 19.063604 n.a. n.a. 1.016493569742 -2.4870273 0.00000800585161 0.7540166 153.0103 /L 26.9907 15.2/ 93.1251 n.a. n.a. 74620.189 82.308064 5.9660106 >..... Elevation Cut-off Requested .....< 2025-Jul-13 10:20 t 22 50 37.37 -34 55 42.0 171.292257 16.861680 n.a. n.a. 1.016483773952 -4.0002276 0.00000861319766 1.8219209 134.5597 /L 45.4411 23.7/ 92.8879 n.a. n.a. 67517.979 89.371986 14.533249 >..... Elevation Cut-off Requested .....< 2025-Jul-13 12:00 Cr 23 50 12.15 -45 00 19.2 180.025843 7.403401 n.a. n.a. 1.016471162692 -4.9612975 0.00001231183284 2.2124753 122.7878 /L 57.2127 38.8/ 92.6336 n.a. n.a. 46585.218 97.778133 17.700505 >..... Elevation Cut-off Requested .....< 2025-Jul-14 06:30 r 15 50 08.89 -40 50 13.9 207.939610 3.936956 n.a. n.a. 1.016461336309 1.2974701 0.00001423277145 -4.6364622 129.4463 /T 50.5518 88.7/ 87.1367 n.a. n.a. 32613.921 99.225464 -39.56518 >..... Elevation Cut-off Requested .....< 2025-Jul-14 08:10 r 16 41 03.24 -27 20 15.0 224.063060 9.453433 n.a. n.a. 1.016459550834 -0.5799580 0.00001132226709 -4.9259702 140.4045 /T 39.5938 81.9/ 86.7567 n.a. n.a. 39032.856 103.76772 -42.67685 >..... Elevation Cut-off Requested .....< 2025-Jul-14 09:50 r 18 06 51.86 -22 51 40.7 229.562264 10.858124 n.a. n.a. 1.016453564528 -2.3793292 0.00001072138334 -4.3030749 159.7159 /T 20.2826 63.6/ 86.4125 n.a. n.a. 45202.968 110.85842 -36.29537 >..... Elevation Cut-off Requested .....< 2025-Jul-14 11:30 Nr 19 53 01.41 -29 46 09.7 224.079154 6.472274 n.a. n.a. 1.016443844525 -3.8532041 0.00001280526182 -2.6247607 170.8989 /L 9.1019 41.6/ 86.0741 n.a. n.a. 43911.653 119.43489 -21.11107 >..... Elevation Cut-off Requested .....< 2025-Jul-15 04:30 Ar 20 45 20.31 -29 12 34.0 127.865242 -0.108118 n.a. n.a. 1.016422756398 1.7186539 0.00001699753811 2.7075899 162.9110 /L 17.0895 41.3/ 79.6429 n.a. n.a. 33051.983 54.422826 21.741885 >..... Elevation Cut-off Requested .....< 2025-Jul-15 06:10 t 22 33 23.35 -20 20 03.1 120.232640 4.824486 n.a. n.a. 1.016421800662 -0.0964227 0.00001372609184 4.5193759 139.1382 /L 40.8627 17.5/ 79.0345 n.a. n.a. 34442.200 63.113629 38.341252 >..... Elevation Cut-off Requested .....< 2025-Jul-15 07:50 t 00 13 11.16 -19 17 20.8 119.553622 5.646941 n.a. n.a. 1.016416707089 -1.9042242 0.00001326016138 5.5252938 116.0650 /L 63.9357 19.2/ 78.5051 n.a. n.a. 29497.112 73.352901 49.447379 >..... Elevation Cut-off Requested .....< 2025-Jul-15 09:30 t 01 24 56.08 -29 13 17.8 131.224343 3.207193 n.a. n.a. 1.016407779188 -3.4561791 0.00001471821859 5.6058358 103.1145 /L 76.8859 38.1/ 78.0404 n.a. n.a. 26058.834 77.537348 50.408706 >..... Elevation Cut-off Requested .....< 2025-Jul-16 04:00 Nt 17 54 10.62 -46 27 03.6 160.812766 2.019077 n.a. n.a. 1.016373146881 3.3206440 0.00001546199676 -0.8429106 146.7905 /T 33.2078 90.8/ 70.3010 n.a. n.a. 38769.003 65.481354 -6.631017 >..... Elevation Cut-off Requested .....< 2025-Jul-16 05:40 t 19 05 26.34 -37 39 53.4 162.981621 12.144496 n.a. n.a. 1.016375929413 1.7862468 0.00001018255307 0.1143486 161.9093 /T 18.0896 77.9/ 69.5147 n.a. n.a. 59084.304 73.594510 0.9062786 >..... Elevation Cut-off Requested .....< 2025-Jul-16 07:20 t 20 37 59.13 -31 08 39.4 162.668174 18.908449 n.a. n.a. 1.016374912369 -0.0050017 0.00000803975050 1.5018583 164.1325 /L 15.8684 58.7/ 68.8206 n.a. n.a. 73094.355 80.772884 11.943175 >..... Elevation Cut-off Requested .....< 2025-Jul-16 09:00 t 22 01 49.91 -35 48 50.6 167.345015 15.255472 n.a. n.a. 1.016369792242 -1.8065811 0.00000909474654 2.3985836 146.3878 /L 33.6132 47.5/ 68.2174 n.a. n.a. 62368.248 87.787634 19.285160 >..... Elevation Cut-off Requested .....< 2025-Jul-16 10:40 At 22 53 32.78 -46 32 53.5 177.965123 5.812584 n.a. n.a. 1.016360826765 -3.3706684 0.00001314427271 2.5579777 134.0417 /L 45.9590 51.3/ 67.6864 n.a. n.a. 42900.147 96.617705 20.572670 >..... Elevation Cut-off Requested .....< 2025-Jul-17 05:10 r 14 48 08.72 -39 37 37.8 207.458876 5.548324 n.a. n.a. 1.016322321389 3.4058386 0.00001328502794 -4.4890269 115.0667 /T 64.9314 137.9/ 58.9820 n.a. n.a. 35656.933 98.960529 -38.09381 >..... Elevation Cut-off Requested .....< 2025-Jul-17 06:50 r 15 42 59.89 -27 00 11.8 222.406414 11.086743 n.a. n.a. 1.016325048798 1.8829621 0.00001061287429 -4.6640158 124.7375 /T 55.2607 135.5/ 58.1358 n.a. n.a. 43421.529 103.99371 -39.93698 >..... Elevation Cut-off Requested .....< 2025-Jul-17 08:30 r 17 13 20.74 -24 30 24.1 225.795145 11.741375 n.a. n.a. 1.016323983406 0.0848961 0.00001035297917 -3.8308352 144.7020 /T 35.2963 116.9/ 57.3937 n.a. n.a. 49368.084 111.53030 -31.79814 >..... Elevation Cut-off Requested .....< 2025-Jul-17 10:10 r 18 58 37.60 -32 32 15.4 219.957934 6.130724 n.a. n.a. 1.016318776018 -1.7410119 0.00001297594771 -2.0561426 164.4111 /T 15.5883 94.8/ 56.7516 n.a. n.a. 44578.366 119.48686 -16.38242 >..... Elevation Cut-off Requested .....< 2025-Jul-18 03:10 Ct 19 46 57.07 -26 33 07.0 124.436202 0.110502 n.a. n.a. 1.016272420650 3.7930393 0.00001684008930 3.1694523 174.4711 /T 5.5281 93.2/ 48.8663 n.a. n.a. 32358.951 55.241298 25.699524 >..... Elevation Cut-off Requested .....< 2025-Jul-18 04:50 t 21 35 49.32 -18 31 20.4 117.167020 4.157462 n.a. n.a. 1.016275873962 2.3510068 0.00001412353910 4.8832509 154.9502 /L 25.0508 68.1/ 47.8438 n.a. n.a. 31669.614 64.782999 42.090493 >..... Elevation Cut-off Requested .....< 2025-Jul-18 06:30 t 23 12 13.83 -19 16 42.2 118.338653 4.355141 n.a. n.a. 1.016275639850 0.5647436 0.00001400414643 5.7001778 132.7141 /L 47.2867 49.9/ 46.8967 n.a. n.a. 26692.427 74.879384 51.597819 >..... Elevation Cut-off Requested .....< 2025-Jul-18 08:00 r 14 54 21.34 -14 07 03.0 251.936125 -0.044255 n.a. n.a. 1.016269801742 1.9868521 0.00001697553592 -5.8562646 109.7060 /T 70.2917 164.1/ 46.1312 n.a. n.a. 21154.424 106.28519 -53.45237 2025-Jul-18 08:10 t 00 20 38.20 -30 22 01.3 131.338144 1.755620 n.a. n.a. 1.016271206143 -1.3199476 0.00001566592476 5.6841625 119.2435 /L 60.7571 49.1/ 46.0518 n.a. n.a. 24003.458 77.966017 51.352596 >..... Elevation Cut-off Requested .....< >..... Daylight Cut-off Requested .....< >..... Elevation Cut-off Requested .....< 2025-Jul-19 04:20 At 18 20 24.32 -35 04 25.3 157.571556 13.007920 n.a. n.a. 1.016213018401 3.9374912 0.00000985997393 0.8665125 155.0858 /T 24.9128 127.4/ 36.8402 n.a. n.a. 60576.710 71.827979 6.8486190 >..... Elevation Cut-off Requested .....< 2025-Jul-19 06:00 t 19 57 21.51 -29 58 02.7 156.299843 18.077473 n.a. n.a. 1.016216450329 2.4532602 0.00000825724650 2.3282961 170.8546 /L 9.1452 107.9/ 35.8498 n.a. n.a. 68902.727 79.069230 18.708403 >..... Elevation Cut-off Requested .....< 2025-Jul-19 07:40 t 21 15 06.64 -36 39 25.7 163.177259 13.326969 n.a. n.a. 1.016216071967 0.6053634 0.00000974245024 2.9838064 156.3426 /L 23.6583 95.2/ 34.9440 n.a. n.a. 56257.897 85.947371 24.249752 >..... Elevation Cut-off Requested .....< 2025-Jul-19 09:20 t 21 59 02.10 -48 03 34.0 175.675614 4.135649 n.a. n.a. 1.016211332882 -1.3512087 0.00001410641233 2.9119259 143.0578 /L 36.9429 93.2/ 34.1460 n.a. n.a. 39151.200 95.160615 23.569663 >..... 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 Inquiries : Jon.D.Giorgini@jpl.nasa.gov ***************************************************************************************************************************************************************************************************************************************************