Key to Geocentric Ephemeris of the Planets








An ephemeris is a table of values that gives 
the positions of astronomical objects in the sky over a range of times, 
while geocentric means "as seen from Earth's center." 
The following table is a key to the geocentric ephemeris of the planets 
and includes a description of each column in these tables.







   

Key to Geocentric Ephemeris of the Planets
   

   

Column
Heading
Definition/Description
   



   

1
Date
(0 UT)		
Calendar Date (Gregorian).

All ephemeris positions are for 00:00:00 UTC

(Coordinated Universal Time).		
   

   

2
Apparent
R.A.		
Apparent Right Ascension of the planet for the true equator 

      and equinox of date (hours, minutes, seconds).		
   

   

3
Apparent
Declination		
Apparent Declination of the planet for the true equator  

      and equinox of date (degrees, arc-minutes, arc-seconds).		
   

   

4
Distance
to Earth		
Distance of the planet from Earth in astronomical units 

      (1 a.u. = 149,597,871 km).		
   

   

5
Distance
to Sun		
Distance of the planet from the Sun in astronomical units 
 
      (1 a.u. = 149,597,871 km).		
   

   

6
App.
Mag.		
Apparent Visual Magnitude of the planet.
   

   

7
Ang.
Diam.		
Apparent Angular Diameter of the planet (arc-seconds).
   

   

8
Phase
Illum.		
Phase Illumination

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

   

9
Phase
Angle		
Phase Angle is the Sun-planet-Earth angle.

      It is the angle between the Sun and Earth as seen from the planet (degrees).		
   

   

10
S.E.
Long.		
Sub-Earth Longitude of the central point of the planet's disk (degrees).
   

   

11
S.E.
Lat.		
Sub-Earth Latitude of the central point of the planet's disk (degrees).
   

   
   

12
P.A.
Axis		
Position Angle of the planet's rotation axis, 
      measured eastwards (counter-clockwise) in the sky 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 0°, 90°, 180°, and 270° correspond to the beginning of
      spring, summer, autumn, and winter, in the planet's northern hemisphere.

   

   

14
Solar
Elong.		
Solar Elongation of the planet. 

      Defined as geocentric angular position of the planet with respect to the Sun (degrees).

      'E' is east (evening sky) and 'W' is west (morning sky).		
   




















Links to Geocentric Ephemerides for the Sun, Moon and Planets












   Geocentric Ephemerides for the Sun, Moon and Planets






   Sun
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Moon
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Mercury
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Venus
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Mars
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Jupiter
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Saturn
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Uranus
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 




   Neptune
    2011 
    2012 
    2013 
    2014 
    2015 
    2016 
    2017 
    2018 
    2019 
    2020 
    2021 
    2022 












Return to: Planetary Ephemeris Data