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HORIZONS Web-Interface
This tool provides a web-based limited interface to JPL's HORIZONS system which can be used to generate ephemerides for solar-system bodies. Full access to HORIZONS features is available via the primary telnet interface. HORIZONS system news shows recent changes and improvements. A web-interface tutorial is available to assist new users.
### Current Settings
Ephemeris Type [change] : | VECTORS
Target Body [change] : | Mars [499]
Coordinate Origin [change] : | Solar System Barycenter (SSB) [500@0]
Time Span [change] : | Start=2015-08-29, Stop=2015-08-30, Step=1 d
Table Settings [change] : | output units=KM-S
Display/Output [change] : | default (formatted HTML)
### Object Data Page
     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
### Results
    *******************************************************************************
    Ephemeris / WWW_USER Wed May 23 05:30:58 2018 Pasadena, USA      / Horizons
    *******************************************************************************
    Target body name: Mars (499)                      {source: mar097}
    Center body name: Solar System Barycenter (0)     {source: DE431mx}
    Center-site name: BODY CENTER
    *******************************************************************************
    Start time      : A.D. 2015-Aug-29 00:00:00.0000 TDB
    Stop  time      : A.D. 2015-Aug-30 00:00:00.0000 TDB
    Step-size       : 1440 minutes
    *******************************************************************************
    Center geodetic : 0.00000000,0.00000000,0.0000000 {E-lon(deg),Lat(deg),Alt(km)}
    Center cylindric: 0.00000000,0.00000000,0.0000000 {E-lon(deg),Dxy(km),Dz(km)}
    Center radii    : (undefined)
    Output units    : KM-S
    Output type     : GEOMETRIC cartesian states
    Output format   : 3 (position, velocity, LT, range, range-rate)
    Reference frame : ICRF/J2000.0
    Coordinate systm: Ecliptic and Mean Equinox of Reference Epoch
    *******************************************************************************
    JDTDB
       X     Y     Z
       VX    VY    VZ
       LT    RG    RR
    *******************************************************************************
    $$SOE
    2457263.500000000 = A.D. 2015-Aug-29 00:00:00.0000 TDB
     X =-1.176389005286295E+08 Y = 2.135936464902488E+08 Z = 7.350773685787022E+06
     VX=-2.027713823922661E+01 VY=-9.661960006152405E+00 VZ= 2.949753324972204E-01
     LT= 8.137541408244299E+02 RG= 2.439573540854340E+08 RR= 1.327343774893074E+00
    2457264.500000000 = A.D. 2015-Aug-30 00:00:00.0000 TDB
     X =-1.193868060069073E+08 Y = 2.127515985562028E+08 Z = 7.376008388681322E+06
     VX=-2.018342979711013E+01 VY=-9.829739376784953E+00 VZ= 2.891593689697625E-01
     LT= 8.141346208607908E+02 RG= 2.440714191307546E+08 RR= 1.313039007239388E+00
    $$EOE
    *******************************************************************************
    Coordinate system description:

      Ecliptic and Mean Equinox of Reference Epoch

        Reference epoch: J2000.0
        XY-plane: plane of the Earth's orbit at the reference epoch
                  Note: obliquity of 84381.448 arcseconds wrt ICRF equator (IAU76)
        X-axis  : out along ascending node of instantaneous plane of the Earth's
                  orbit and the Earth's mean equator at the reference epoch
        Z-axis  : perpendicular to the xy-plane in the directional (+ or -) sense
                  of Earth's north pole at the reference epoch.

      Symbol meaning:

        JDTDB    Julian Day Number, Barycentric Dynamical Time
          X      X-component of position vector (km)
          Y      Y-component of position vector (km)
          Z      Z-component of position vector (km)
          VX     X-component of velocity vector (km/sec)
          VY     Y-component of velocity vector (km/sec)
          VZ     Z-component of velocity vector (km/sec)
          LT     One-way down-leg Newtonian light-time (sec)
          RG     Range; distance from coordinate center (km)
          RR     Range-rate; radial velocity wrt coord. center (km/sec)

    Geometric states/elements have no aberrations applied.

     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)
                      http://ssd.jpl.nasa.gov/?horizons
                      telnet ssd.jpl.nasa.gov 6775    (via command-line)
         Author     : Jon.D.Giorgini@jpl.nasa.gov
    *******************************************************************************
| 2018-May-23 05:30 UT (server date/time) |  |
Site Manager: | Ryan S. Park
Webmaster: | Alan B. Chamberlin