THE NAUTICAL ALMANAC

Taranaki Daily News, 6 April 1932, Page 2

THE NAUTICAL ALMANAC

INTRICATE CALCULATIONS. REMARKABLE PROGRESS MADE. While thousands of ships are sailing the seven seas, a vast work is being performed efficiently and silently for their navigators. Each year is produced at Greenwich, England, a new edition of the Abridged Nautical Almanac, which is specially designed for use at sea. The complete Almanac contains much further information without which astronomers could not work at all. Its predictions are based on their former observations, and in turn form the standard with which their new observations are compared. Some idea of the importance and magnitude of the work undertaken in the production of the Nautical Almanac is contained in an article published in the New Zealand News of February 9. • “Under the direction of Dr. L. J. Comrie, the superintendent, who is a New Zealander, remarkable progress has been made in converting His Majesty’s Nautical Almanac Office at Greenwich into the most highly mechanised department of its kind in the world,” states the article. “Already students of calculating machines come from the ends of the earth to observe the methods by which these machines are adapted to the needs of science and made to grapple with the most intricate calculations.

“Greenwich is the hub of the nautical universe. Every navigator who wishes to determine the position of his vessel must know three things—Greenwich mean time, the altitude of the sun or some other heavenly body, and the celestial position of that body, known technically as its right ascension and declination.

“The first is obtained from a clock, checked several times daily by wireless time signals originating from Greenwich; the second results from a sextant observation; while the third is given iby the Seaman’s Bible—the Nautical Almanac, and the safety of all shipping is dependent on the accuracy of its figures. “The Royal Observatory at Greenwich was founded more than 250 years ago to facilitate the determination of longitude at sea, and the Nautical Almanac was first published in 1767 to give sailors the necessary positions of the sun, moon, planets ■ and stars. Since that time there has been a continuous gain in accuracy until to-day certain of the necessary tables can be confidently made ahead as far as 2000 A.D., with the conviction that no new accession of knowledge can make them out of date.