Planetary Ephemeris Data

The creation of modern ephemerides involves the fitting to a wide variety of astronomical measurements (observations).
This website presents the sets of observations that are currently being used in creation and improvement of modern planetary and lunar ephemerides.

This page is currently maintained by

Present Home Page for the IAU Commission 4 (Ephemerides) : ""

Meridian Circle Timings (Transits)

Photographic Astrometry of outer planets and satellites

Photographic Astrometry of Pluto

CCD Astrometry of the Outer Planets and Satellites

Astrolabe Observations

Radar Ranging

Spacecraft encounter estimates

* Spacecraft 3-D Observations * Format

Spacecraft VLBI

Venus Spacecraft Doppler

Mars Spacecraft Ranging

Mars Spacecraft Doppler (Differenced Range)

Cassini Spacecraft Range

DSN Station Locations

Lunar Laser Ranging

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Last modified: 2012 October 09