# Key to Geocentric Ephemeris of the Sun

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 Sun and includes a description of each column in the ephemeris tables.

Key to Geocentric Ephemeris of the Sun | ||

Column | Heading | Definition/Description |

1 | Date (0 DT) |
Calendar Date (Gregorian).
All ephemeris positions are for 00:00:00 UTC (Coordinated Universal Time). |

2 | JD (2440000+) |
Abbreviated Julian Day Number.
To convert to full Julian Day Number, add 2440000. The Julian Day Number is defined as the number of days elapsed since Greenwich Mean Noon on 0 January 4713 BCE. |

3 | App. GST | Apparent Greenwich Mean Sidereal Time at 00:00:00 UTC (Coordinated Universal Time). |

4 | Equation of Time |
The difference between apparent solar time and mean solar time. |

5 | Apparent R.A. |
Apparent Right Ascension of the Sun for the true equator and equinox of date (hours, minutes, seconds). |

6 | Apparent Declination |
Apparent Declination of the Sun for the true equator and equinox of date (degrees, arc-minutes, arc-seconds). |

7 | Distance | Distance of the Sun from Earth in astronomical units (1 a.u. = 149,597,871 km). |

8 | Ang. Diam. |
Apparent Angular Diameter of the Sun (arc-seconds). |

9 | Hel. Lng. |
Heliographic Longitude of the central point of the solar disk (degrees). |

10 | Hel. Lat. |
Heliographic Latitude of the central point of the solar disk (degrees). |

11 | P.A. Axis |
Position Angle of the Sun's rotation axis, measured eastwards (counter-clockwise) on the sky from the celestial north point of the solar disk (degrees). |

## 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 |