History of The Astronomical Almanac
Astronomical Applications Dept. Astronomical Applications Dept.
 
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Picture of the 2013 Astronomical Almanac The Astronomical Almanac is the direct descendant of the British and American navigational almanacs. The British Nautical Almanac and Astronomical Ephemeris had been published since 1766, and was renamed The Astronomical Ephemeris in 1960. The American Ephemeris and Nautical Almanac had been published since 1852. In 1981 the British and American publications were combined under the title The Astronomical Almanac.

Chronology:
1766 First edition of The Nautical Almanac and Astronomical Ephemeris, published by Astronomer Royal of England, with data for 1767.
1852 First edition of The American Ephemeris and Nautical Almanac, with data for 1855. The US book publishes part of its data using the prime meridian of Washington, and part using the prime meridian of Greenwich.
1912 U.S. Congress authorizes the international exchange of data. The official collaboration between the US and UK begins and continues today.
1941 Almanacs adopt FK3 as the fundamental reference system
1960 The title The Astronomical Ephemeris replaces, without loss of continuity of content, the previous UK title The Nautical Almanac and Astronomical Ephemeris. The Astronomical Ephemeris and the American Ephemeris and Nautical Almanac become identical in content. The US and UK each produce about 50% of the text.
1961 First edition of the Explanatory Supplement to the Astronomical Almanac is published.
1964 Almanacs adopt FK4 as the fundamental reference system.
1968 International Astronomical Union 1964 constants adopted.
1981 Both almanacs change their name to The Astronomical Almanac.
1981 Stars and Stellar Systems Section added.
1984 International Astronomical Union 1976 constants and FK5 (J2000) system adopted.
1984 Ephemeris Time (ET) replaced with Barycentric Dynamic Time (TDB) and Terrestrial Dynamical Time (TDT).
1984 DE200/LE200 Jet Propulsion Laboratory planetary ephemerides adopted.
1992 Second edition of the Explanatory Supplement to the Astronomical Almanac is published.
2003 DE405/LE405 Jet Propulsion Laboratory planetary ephemerides adopted. Major revision of minor planet section. The Hipparcos Catalogue is the basis for the stellar data, replacing the FK5.
2006 IAU/IERS "interim" precession and nutation models incorporated.
2009 Finalized IAU precession and nutation models incorporated.
2012 Third edition of the Explanatory Supplement to the Astronomical Almanac is published.
2013 Pluto data reorganized and added to newly named Section G, Dwarf Planets & Small Solar System Bodies.