*******************************************************************************
 Revised: April 12, 2021             Mercury                            199 / 1

 PHYSICAL DATA (updated 2021-Apr-12):
  Vol. Mean Radius (km) =  2440+-1        Density (g cm^-3)     = 5.427
  Mass x10^23 (kg)      =     3.302       Volume (x10^10 km^3)  = 6.085  
  Sidereal rot. period  =    58.6463 d    Sid. rot. rate (rad/s)= 0.00000124001
  Mean solar day        =   175.9421 d    Core radius (km)      = ~1600 
  Geometric Albedo      =     0.106       Surface emissivity    = 0.77+-0.06
  GM (km^3/s^2)         = 22031.86855     Equatorial radius, Re = 2440 km
  GM 1-sigma (km^3/s^2) =                 Mass ratio (Sun/plnt) = 6023682
  Mom. of Inertia       =     0.33        Equ. gravity  m/s^2   = 3.701     
  Atmos. pressure (bar) = < 5x10^-15      Max. angular diam.    = 11.0"   
  Mean Temperature (K)  = 440             Visual mag. V(1,0)    = -0.42 
  Obliquity to orbit[1] =  2.11' +/- 0.1' Hill's sphere rad. Rp = 94.4 
  Sidereal orb. per.    =  0.2408467 y    Mean Orbit vel.  km/s = 47.362 
  Sidereal orb. per.    = 87.969257  d    Escape vel. km/s      =  4.435
                                 Perihelion  Aphelion    Mean
  Solar Constant (W/m^2)         14462       6278        9126
  Maximum Planetary IR (W/m^2)   12700       5500        8000
  Minimum Planetary IR (W/m^2)   6           6           6
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Ephemeris / WWW_USER Sat Apr 17 17:27:59 2021 Pasadena, USA      / Horizons
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Target body name: Mercury (199)                   {source: DE441}
Center body name: Solar System Barycenter (0)     {source: DE441}
Center-site name: BODY CENTER
*******************************************************************************
Start time      : A.D. 2020-Jan-02 00:00:00.0000 TDB
Stop  time      : A.D. 2020-Jan-02 00:01:00.0000 TDB
Step-size       : 60 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-D
Output type     : GEOMETRIC cartesian states
Output format   : 3 (position, velocity, LT, range, range-rate)
Reference frame : ICRF
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JDTDB
   X     Y     Z
   VX    VY    VZ
   LT    RG    RR
*******************************************************************************
$$SOE
2458850.500000000 = A.D. 2020-Jan-02 00:00:00.0000 TDB 
 X =-6.706875219569503E+06 Y =-6.044461660946982E+07 Z =-3.175166955207460E+07
 VX= 3.346870045424018E+06 VY=-1.701434977841626E+04 VZ=-3.560819216270942E+05
 LT= 2.648646033796148E-03 RG= 6.860541065849553E+07 RR=-1.473997213270023E+05
$$EOE
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Coordinate system description:

  International Celestial Reference Frame (ICRF)

    The ICRF is an adopted reference frame whose axes are defined relative to 
    fixed extragalactic radio sources distributed across the sky.

    The ICRF was aligned with the prior FK5/J2000 dynamical system at the ~0.02 
    arcsecond level but is not identical and has no associated standard epoch.

  Symbol meaning [1 day=86400.0 s]:

    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/day)                           
      VY     Y-component of velocity vector (km/day)                           
      VZ     Z-component of velocity vector (km/day)                           
      LT     One-way down-leg Newtonian light-time (day)
      RG     Range; distance from coordinate center (km)
      RR     Range-rate; radial velocity wrt coord. center (km/day)

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  : https://ssd.jpl.nasa.gov/
     Documentation: https://ssd.jpl.nasa.gov/?horizons_doc
     Connect      : https://ssd.jpl.nasa.gov/?horizons (browser)
                    telnet ssd.jpl.nasa.gov 6775       (command-line)
                    e-mail command interface available
                    Script and CGI interfaces available
     Author       : Jon.D.Giorgini@jpl.nasa.gov
*******************************************************************************

!$$SOF
command = 199
TABLE_TYPE = 'VECTORS'
REF_PLANE = 'FRAME'
START_TIME = '2020-Jan-02 00:00:00.0000'
STOP_TIME = '2020-Jan-02 00:01:00.0000'
STEP_SIZE = '1 hours'
OUT_UNITS = 'KM-D'
CENTER = 500@0