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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] : | Earth [Geocenter] [399]
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: Jul 31, 2013                  Earth                                399

    PHYSICAL PROPERTIES (revised Sep 18, 2013):
     Mean radius, km          = 6371.01+-0.01   Mass, 10^24 kg = 5.97219+-0.0006
     Equ. radius, km          = 6378.14+-0.01   Mass layers:
     Polar axis, km           = 6356.752          Atmos          = 5.1   x 10^18 kg
     Flattening               = 1/298.257         oceans         = 1.4   x 10^21 kg
     Density, gm cm^-3        = 5.515             crust          = 2.6   x 10^22 kg
     J2  (GEM T2, 1990)       = 0.0010826265      mantle         = 4.043 x 10^24 kg
     gp, m s^-2 (polar)       = 9.8321863685      outer core     = 1.835 x 10^24 kg
     ge, m s^-2 (equatorial)  = 9.7803267715      inner core     = 9.675 x 10^22 kg
     go, m s^-2               = 9.82022         Fluid core rad   = 3480 km
     GM, km^3 s^-2            = 398600.440      Inner core rad   = 1215 km
     Mean rot. rate, rad s^-1 = 7.292115*10^-5  Surface Area:
     Sidereal period, hr      = 23.93419          land           = 1.48 x 10^8 km
     Mean solar day, days     = 1.002738          sea            = 3.62 x 10^8 km
     Moment of inertia        = 0.3308          Love no., k2     = 0.299
     Mean Temperature, K      = 270             Atm. pressure    = 1.0 bar
     Solar constant, W/m^2    = 1367.6          Vis. mag. V(1,0) = -3.86
     Volume, 10^10 km^3       = 108.321         Geometric albedo = 0.367

    DYNAMICAL CHARACTERISTICS:
     Obliquity to orbit, deg  = 23.45           Sidereal period  = 1.0000174  yrs
     Orbit velocity, km s^-1  = 29.7859         Sidereal period  = 365.25636  days
     Mean daily motion, n     = 0.9856474 deg/d Escape velocity  = 11.186 km s^-1
     Hill's sphere radius     = 234.9           Magnetic moment  = 0.61 gauss Rp^3
### Results
    *******************************************************************************
    Ephemeris / WWW_USER Wed May 23 05:34:58 2018 Pasadena, USA      / Horizons
    *******************************************************************************
    Target body name: Earth (399)                     {source: DE431mx}
    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
    *******************************************************************************
    $$SOE
    2457263.500000000 = A.D. 2015-Aug-29 00:00:00.0000 TDB
     X = 1.376368513677354E+08 Y =-6.342242292720988E+07 Z =-2.196418258551881E+04
     VX= 1.203162796791987E+01 VY= 2.691852057718956E+01 VZ=-9.423706264577447E-05
     LT= 5.055043307947790E+02 RG= 1.515463858586119E+08 RR=-3.381301634392637E-01
    2457264.500000000 = A.D. 2015-Aug-30 00:00:00.0000 TDB
     X = 1.386567636393730E+08 Y =-6.108772457269292E+07 Z =-2.196580001194030E+04
     VX= 1.157690924441596E+01 VY= 2.712427563778175E+01 VZ= 4.564582931187999E-05
     LT= 5.054063914656761E+02 RG= 1.515170243864053E+08 RR=-3.415029553896776E-01
    $$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 05:34 UT (server date/time) |  |
Site Manager: | Ryan S. Park
Webmaster: | Alan B. Chamberlin