in Astronomy, tables calculated by astronomers, showing the actual state of the heavens for every day at noon; that is, the places in which all the planets are found at that time. It is from these tables that the eclipses, conjunctions, and aspects of the planets are determined. In England, the Nautical Almanack, or Astronomical Ephemeris, published annually by anticipation, under the direction of the Board of Longitude, is the most considerable work of the kind.