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Example Ephemeris

The text below shows what a typical ephemeris generated by HORIZONS should look like - it was copied and pasted directly out of a browser window. Ephemerides that do not conform to this format cannot be guaranteed to run correctly and are likely to be rejected by the OT.

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 Revised: Sep 28, 2012                 Mars                             499 / 4
 
 GEOPHYSICAL DATA (updated 2009-May-26):
  Mean radius (km)      = 3389.9(2+-4)    Density (g cm^-3)     =  3.933(5+-4)
  Mass (10^23 kg )      =    6.4185       Flattening, f         =  1/154.409
  Volume (x10^10 km^3)  =   16.318        Semi-major axis       =  3397+-4
  Sidereal rot. period  =   24.622962 hr  Rot. Rate (x10^5 s)   =  7.088218
  Mean solar day        =    1.0274907 d  Polar gravity ms^-2   =  3.758
  Mom. of Inertia       =    0.366        Equ. gravity  ms^-2   =  3.71
  Core radius (km)      =  ~1700          Potential Love # k2   =  0.153 +-.017
 
  Grav spectral fact u  =   14 (x10^5)    Topo. spectral fact t = 96 (x10^5)
  Fig. offset (Rcf-Rcm) = 2.50+-0.07 km   Offset (lat./long.)   = 62d / 88d
  GM (km^3 s^-2)        = 42828.3         Equatorial Radius, Re = 3394.0 km 
  GM 1-sigma (km^3 s^-2)= +- 0.1          Mass ratio (Sun/Mars) = 3098708+-9
  
  Atmos. pressure (bar) =    0.0056       Max. angular diam.    =  17.9"
  Mean Temperature (K)  =  210            Visual mag. V(1,0)    =  -1.52
  Geometric albedo      =    0.150        Obliquity to orbit    =  25.19 deg
  Mean sidereal orb per =    1.88081578 y Orbit vel.  km/s      =  24.1309
  Mean sidereal orb per =  686.98 d       Escape vel. km/s      =   5.027
  Hill's sphere rad. Rp =  319.8          Mag. mom (gauss Rp^3) = < 1x10^-4 
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Ephemeris / WWW_USER Mon Feb 25 23:51:53 2013 Pasadena, USA      / Horizons    
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Target body name: Mars (499)                      {source: MAR097}
Center body name: Earth (399)                     {source: DE405}
Center-site name: Atacama Large mm/sub-mm Array (ALMA) Center of Array
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Start time      : A.D. 2012-Nov-20 00:00:00.0000 UT      
Stop  time      : A.D. 2012-Nov-20 01:00:00.0000 UT      
Step-size       : 10 minutes
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Target pole/equ : IAU_MARS                        {East-longitude -}
Target radii    : 3396.2 x 3396.2 x 3376.2 km     {Equator, meridian, pole}    
Center geodetic : 292.245252,-23.016211,5.0748870 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 292.245252,5878.07779,-2480.356 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : High-precision EOP model        {East-longitude +}
Center radii    : 6378.1 x 6378.1 x 6356.8 km     {Equator, meridian, pole}    
Target primary  : Sun                             {source: DE405+DE406}
Vis. interferer : MOON (R_eq= 1737.400) km        {source: DE405}
Rel. light bend : Sun, EARTH                      {source: DE405}
Rel. lght bnd GM: 1.3271E+11, 3.9860E+05 km^3/s^2                              
Atmos refraction: NO (AIRLESS)
RA format       : HMS
Time format     : CAL 
RTS-only print  : NO       
EOP file        : eop.130225.p130519                                           
EOP coverage    : DATA-BASED 1962-JAN-20 TO 2013-FEB-25. PREDICTS-> 2013-MAY-18
Units conversion: 1 AU= 149597870.691 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 )                           
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 Date__(UT)__HR:MN     R.A._(ICRF/J2000.0)_DEC            delta      deldot
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$$SOE
 2012-Nov-20 00:00 Am  18 08 49.57 -24 32 45.2 2.11526724217947   5.4283109
 2012-Nov-20 00:10 Am  18 08 50.96 -24 32 45.0 2.11528902003861   5.4308867
 2012-Nov-20 00:20  m  18 08 52.35 -24 32 44.7 2.11531080675966   5.4327290
 2012-Nov-20 00:30  m  18 08 53.73 -24 32 44.4 2.11533259939253   5.4338340
 2012-Nov-20 00:40  m  18 08 55.12 -24 32 44.1 2.11535439497415   5.4341991
 2012-Nov-20 00:50  m  18 08 56.51 -24 32 43.8 2.11537619053409   5.4338231
 2012-Nov-20 01:00  m  18 08 57.90 -24 32 43.6 2.11539798310023   5.4327065
$$EOE
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Column meaning:
 
TIME

  Prior to 1962, times are UT1. Dates thereafter are UTC. Any 'b' symbol in
the 1st-column denotes a B.C. date. First-column blank (" ") denotes an A.D.
date. Calendar dates prior to 1582-Oct-15 are in the Julian calendar system.
Later calendar dates are in the Gregorian system.

  Time tags refer to the same instant throughout the universe, regardless of
where the observer is located.

  The uniform Coordinate Time scale is used internally. It is equivalent to
the current IAU definition of "TDB". Conversion between CT and the selected
non-uniform UT output scale has not been determined for UTC times after the
next July or January 1st.  The last known leap-second is used over any future
interval.

  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 symbol:

        '*'  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 MARKER (OBSERVING SITE)
  The solar-presence symbol is immediately followed by another marker symbol:

        'm'  Refracted upper-limb of Moon on or above apparent horizon
        ' '  Refracted upper-limb of Moon below apparent horizon OR geocentric
        'r'  Rise    (target body on or above cut-off RTS elevation)
        't'  Transit (target body at or past local maximum RTS elevation)
        's'  Set     (target body on or 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/J2000.0)_DEC =
   J2000.0 astrometric right ascension and declination of target center.
Corrected for light-time. Units: HMS (HH MM SS.ff) and DMS (DD MM SS.f)
 
 delta  deldot =
   Range ("delta") and range-rate ("delta-dot") of target center with respect
to the observer at the instant light seen by the observer at print-time would
have left the target center (print-time minus down-leg light-time); the
distance traveled by a light ray emanating from the center of the target and
recorded by the observer at print-time. "deldot" is a projection of the
velocity vector along this ray, the light-time-corrected line-of-sight from the
coordinate center, and indicates relative motion. A positive "deldot" means the
target center is moving away from the observer (coordinate center). A negative
"deldot" means the target center is moving 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
     Information: http://ssd.jpl.nasa.gov/
     Connect    : telnet://ssd.jpl.nasa.gov:6775  (via browser)
                  telnet ssd.jpl.nasa.gov 6775    (via command-line)
     Author     : Jon.Giorgini@jpl.nasa.gov

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The ALMA OT Team, 2016 Aug 23