• Contents
  • Welcome
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  • Phenomena (incl. eclipses)
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• Errata
  • Errata 2018
  • Errata 2017
  • Errata 2016
  • Errata 2015
  • Errata 2014
  • Errata 2013
  • Errata 2012
  • Errata 2011
  • Errata 2010
  • Errata 2009
  • Errata 2008
  • Errata 2007
  • Errata 2006
  • Errata 2005
  • Errata 2004
  • Errata 2003
  • Errata 2002
  • Errata 2001
• Constants
• Glossary
• Utilities
  • Planetary Geocentric Coordinates
• Additional Info
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Selected astronomical constants are given along with their associated references. Included are values used in the production of The Astronomical Almanac. In some cases, differing sources yield differing values; in those instances more than one value may be given.

• 2021 Selected Astronomical Constants in PDF and ASCII format
• 2020 Selected Astronomical Constants in PDF and ASCII format
• 2019 Selected Astronomical Constants in PDF and ASCII format
• 2018 Selected Astronomical Constants in PDF and ASCII format
• 2017 Selected Astronomical Constants in PDF and ASCII format
• 2016 Selected Astronomical Constants in PDF and ASCII format
• 2015 Selected Astronomical Constants in PDF and ASCII format
• 2014 Selected Astronomical Constants in PDF and ASCII format
• 2013 Selected Astronomical Constants in PDF and ASCII format
• 2012 Selected Astronomical Constants in PDF and ASCII format
• 2011 Selected Astronomical Constants in PDF and ASCII format
• 2010 Selected Astronomical Constants in PDF and ASCII format
• 2009 Selected Astronomical Constants in PDF and ASCII format
• 2008 Selected Astronomical Constants in PDF and ASCII format
• 2007 Selected Astronomical Constants in PDF and ASCII format
• 1976 IAU Constants in PDF