Abstract
AT the annual visitation of the Royal Observatory, Greenwich, by the Board of Visitors on Saturday, June 1, the Astronomer Royal presented his report, which describes the work of the observatory during the year ended on May 10. The observations with the transit circle numbered nearly nine thousand, embracing the sun, moon, planets (of which special attention was paid to Vesta, owing to its value for determining the equator point), fundamental stars, and stars needed for comparison with Eros at the time of its near approach to the earth in 1930–31. The correction to the longitude of the moon as calculated from Brown's tables is +5.51″from the limb and +5.83Prime; from the crater Mosting A. The correction has been diminishing at the rate of a. third of a second por annum since Brown's tables were introduced into the almanacs in 1923. The early observations of the sun and moon, from 1751 onwards, have been re-reduced; it is found that the longitudes deduced from the declinations are more trustworthy in the early years than those from the right ascensions. The results give support to the theory that there are variations in the earth's rate of rotation; they also indicate a secular acceleration of the sun's longitude, the amount of which is +0.78Prime;in a century.
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CROMMELIN, A. Annual Visitation of the Royal Observatory, Greenwich. Nature 123, 891 (1929). https://doi.org/10.1038/123891a0
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DOI: https://doi.org/10.1038/123891a0