NASA Reference Publication 1349

Twelve Year Planetary Ephemeris: 1995 - 2006

Fred Espenak

SECTION 2: Geocentric Ephemeris for the Major Planets

 Column  Heading      Definition/Description

     1      Date          Calendar Date (Gregorian). 
           (0 DT)         All ephemeris positions are for 00:00:00 DT
                          (Terrestrial Dynamical Time).     

     2       RA           Apparent Right Ascension of Planet for true equator and
           (h m s)        equinox of date (hours, minutes, seconds).

     3      Dec           Apparent Declination of Planet for true equator and
          (d  '  ")       equinox of date (degrees, arcminutes, arcseconds).

     4     Delta          Distance of the Planet from Earth in astronomical units
          (a.u.)          (1 a.u. = 1.496x108 km).

     5      Rho           Distance of the Planet from the Sun in astronomical units
           (a.u.)         (1 a.u. = 1.496x108 km).

     6      RV            Geocentric Radial Velocity of the Planet (kilometers per
          (km/s)          second).
          
     7       V            Apparent Visual Magnitude of the Planet.

     8     Diam           Apparent Angular Diameter of the Planet (arcseconds).
           (")

     9     Phase          Fractional area (or diameter) of the Planet's apparent
                          disk illuminated by sunlight.

     10     S.E.          Sub-Earth Latitude of the central point of the Planet's
            Lat           disk (degrees).

     11     S.E.          Sub-Earth Longitude of the central point of the Planet's
            Long          disk (degrees).  Also called CML (Central Meridian
                          Longitude).

     12     P.A.          Position Angle of the Planet's rotation axis, measured
            Axis          eastwards (counter-clockwise) from the celestial north
                          point of the planetary disk (degrees).

     13      Ls           Planetocentric Orbital Longitude of the Sun, measured
                          eastward in the Planet's orbital plane from Planet's
                          vernal equinox (degrees). Values of 0š, 90š,
                          180š, and 270š correspond to the beginning of
                          spring, summer, autumn, and winter, in planet's northern
                          hemisphere.

     14     Solar         Solar Elongation of the Planet. Defined as geocentric
            Elong         angular position of Planet with respect to the Sun
                          (degrees).   'E' is east (evening sky) and 'W' is west
                          (morning sky).

Return to Twelve Year Planetary Ephemeris Directory

Webmaster: Fred Espenak Planteary Systems Laboratory - Code 693 Email: espenak@lepvax.gsfc.nasa.gov NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA