API VERSION: 1.2 API SOURCE: NASA/JPL Horizons API ******************************************************************************* Revised: Dec 06, 2024 Spektr-R Telescope (Spacecraft) -557 (Earth orbiting) http://www.spaceflightnow.com/news/n1107/18spektr/ BACKGROUND: Russian Earth-orbiting radio telescope funded by Russian Astro Space Center. It was launched from the Baikonur Cosmodrome on July 18, 2011 at 02:31 UTC by a Zenit-3M launcher with Fregat-SB upper stage. MISSION OBJECTIVES: The primary scientific goal of Spektr-R over the planned 5-year mission is the study of astronomical objects at an angular resolution of a few millionths of an arcsecond. This is accomplished by using the satellite interferometrically in conjunction with ground-based observatories, including Arecibo and Greenbank. The primary targets are extragalactic. Characteristics of near-Earth and interplanetary plasma will also be studied. Wavelengths used are 1.35-6.0, 18.0 and 92.0 cm. PHYSICAL DATA: Mass : 3295 kg Diameter: 10 m SPACECRAFT TRAJECTORY: Perigee: ~ 10,000 km Apogee : ~390,000 km TRAJECTORY: The IKI (Russian Space Research Institute) provided an official trajectory for Nov 1-16 (2011). TLEs are used for other times, and are low-precision, especially during the following intervals which are extrapolations over data gaps: 2011: 2012: 2013: Jul 22 - Aug 04 Feb 26 - Apr 24 Jan 16 - Jun 02 Aug 12 - Oct 04 May 11 - May 29 Jul 04 - Jul 14 Dec 09 - Feb 17 (2012) Jun 12 - Aug 30 Oct 16 - Nov 02 Sep 08 - Jan 08 (2013) Dec 24 - Jan 10 Jan 19 - Feb 22 May 09 - May 27 Trajectory name Start Stop ------------------------------ ----------------- ----------------- TLEs 2011-Jun-18 06:09 2011-Nov-01 11:01 spectr_111101_111116_111102 2011-Nov-01 11:01 2011-Nov-16 01:07 TLEs 2011-Nov-16 01:07 Current ******************************************************************************* ******************************************************************************* Ephemeris / API_USER Mon Dec 9 17:17:58 2024 Pasadena, USA / Horizons ******************************************************************************* Target body name: Spektr-R Observatory (spacecraft) (-557) {source: spektr-r_MERGED} Center body name: Earth (399) {source: DE441} Center-site name: Swan Reach Imaging, Glenalta ******************************************************************************* 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 : 139.5701, -34.5440227, .056888 {E-lon(deg),Lat(deg),Alt(km)} Center cylindric: 139.5701,5259.32258,-3596.34777 {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.241209.p250307 EOP coverage : DATA-BASED 1962-JAN-20 TO 2024-DEC-09. PREDICTS-> 2025-MAR-06 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 .....< 2024-Nov-30 16:20 09 15 50.07 +46 00 39.4 29.348608 -0.020957 n.a. n.a. 0.987270472978 -0.3636024 0.00233176266141 -0.0375706 117.7046 /L 62.1756 114.0/ 0.4035 n.a. n.a. 6.2019199 199.80788 -12.12756 2024-Nov-30 16:30 09 15 47.86 +45 59 39.4 27.915856 0.985918 n.a. n.a. 0.987269019437 -0.3643824 0.00233163661211 -0.0309728 117.7160 /L 62.1642 114.2/ 0.3936 n.a. n.a. 6.6389618 202.22142 -9.396653 2024-Nov-30 16:40 09 15 45.27 +45 58 36.3 26.450309 1.948109 n.a. n.a. 0.987267562782 -0.3651617 0.00233153771909 -0.0240184 117.7285 /L 62.1518 114.3/ 0.3840 n.a. n.a. 7.0897349 204.14848 -6.852265 2024-Nov-30 16:50 09 15 42.31 +45 57 29.8 24.952575 2.863908 n.a. n.a. 0.987266103014 -0.3659404 0.00233146738171 -0.0167229 117.7419 /L 62.1383 114.4/ 0.3746 n.a. n.a. 7.5494475 205.66566 -4.492169 2024-Nov-30 17:00 09 15 39.02 +45 56 19.9 23.423401 3.731622 n.a. n.a. 0.987264640138 -0.3667185 0.00233142693494 -0.0091030 117.7563 /L 62.1239 114.5/ 0.3655 n.a. n.a. 8.0143049 206.83742 -2.306049 2024-Nov-30 17:10 09 15 35.40 +45 55 06.4 21.863685 4.549579 n.a. n.a. 0.987263174155 -0.3674960 0.00233141764638 -0.0011755 117.7716 /L 62.1087 114.6/ 0.3567 n.a. n.a. 8.4812867 207.71716 -0.279905 2024-Nov-30 17:20 09 15 31.48 +45 53 49.4 20.274481 5.316139 n.a. n.a. 0.987261705068 -0.3682728 0.00233144071382 0.0070416 117.7877 /L 62.0926 114.7/ 0.3482 n.a. n.a. 8.9479739 208.34874 1.6013244 2024-Nov-30 17:30 09 15 27.28 +45 52 28.6 18.657008 6.029706 n.a. n.a. 0.987260232880 -0.3690490 0.00233149726241 0.0155299 117.8046 /L 62.0757 114.8/ 0.3399 n.a. n.a. 9.4124151 208.76812 3.3523174 2024-Nov-30 17:40 A 09 15 22.82 +45 51 04.0 17.012656 6.688739 n.a. n.a. 0.987258757593 -0.3698246 0.00233158834241 0.0242706 117.8221 /L 62.0582 114.9/ 0.3319 n.a. n.a. 9.8730269 209.00480 4.9866471 2024-Nov-30 17:50 A 09 15 18.14 +45 49 35.5 15.342986 7.291765 n.a. n.a. 0.987257279211 -0.3705996 0.00233171492682 0.0332440 117.8403 /L 62.0401 115.0/ 0.3241 n.a. n.a. 10.328518 209.08305 6.5164859 2024-Nov-30 18:00 A 09 15 13.24 +45 48 03.1 13.649729 7.837393 n.a. n.a. 0.987255797736 -0.3713740 0.00233187790932 0.0424302 117.8590 /L 62.0214 115.1/ 0.3167 n.a. n.a. 10.777832 209.02293 7.9525465 2024-Nov-30 18:10 A 09 15 08.16 +45 46 26.6 11.934785 8.324322 n.a. n.a. 0.987254313171 -0.3721479 0.00233207810225 0.0518086 117.8782 /L 62.0022 115.2/ 0.3094 n.a. n.a. 11.220106 208.84109 9.3041463 2024-Nov-30 18:20 N 09 15 02.93 +45 44 46.1 10.200216 8.751360 n.a. n.a. 0.987252825517 -0.3729211 0.00233231623483 0.0613583 117.8978 /L 61.9826 115.3/ 0.3025 n.a. n.a. 11.654635 208.55144 10.579327 2024-Nov-30 18:30 N 09 14 57.55 +45 43 01.5 8.448235 9.117430 n.a. n.a. 0.987251334778 -0.3736938 0.00233259295157 0.0710579 117.9177 /L 61.9627 115.4/ 0.2958 n.a. n.a. 12.080850 208.16563 11.784998 2024-Nov-30 18:40 N 09 14 52.07 +45 41 12.7 6.681194 9.421583 n.a. n.a. 0.987249840957 -0.3744659 0.00233290881070 0.0808858 117.9379 /L 61.9425 115.5/ 0.2894 n.a. n.a. 12.498294 207.69352 12.927073 2024-Nov-30 18:50 Nm 09 14 46.50 +45 39 19.7 4.901570 9.663012 n.a. n.a. 0.987248344055 -0.3752374 0.00233326428306 0.0908201 117.9583 /L 61.9221 115.6/ 0.2832 n.a. n.a. 12.906611 207.14349 14.010608 2024-Nov-30 19:00 Cm 09 14 40.87 +45 37 22.6 3.111941 9.841054 n.a. n.a. 0.987246844076 -0.3760083 0.00233365975085 0.1008386 117.9788 /L 61.9016 115.7/ 0.2772 n.a. n.a. 13.305533 206.52270 15.039914 2024-Nov-30 19:10 Cm 09 14 35.21 +45 35 21.2 1.314972 9.955203 n.a. n.a. 0.987245341021 -0.3767788 0.00233409550676 0.1109187 117.9993 /L 61.8811 115.8/ 0.2715 n.a. n.a. 13.694868 205.83730 16.018669 2024-Nov-30 19:20 Ct 09 14 29.54 +45 33 15.7 359.513384 10.005112 n.a. n.a. 0.987243834893 -0.3775486 0.00233457175331 0.1210380 118.0199 /L 61.8606 115.9/ 0.2661 n.a. n.a. 14.074492 205.09262 16.949999 >..... 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/hrzn_batch.txt scripts https://ssd.jpl.nasa.gov/ftp/ssd/SCRIPTS Author : Jon.D.Giorgini@jpl.nasa.gov ***************************************************************************************************************************************************************************************************************************************************