05/29/2013 08:03 am ET

British Astronomer's Navigation Achievement & Prime Meridian Explained

Magnus Manske, Wikimedia Commons

Some 250 years ago, a British astronomer published the first of a series of guidebooks that would ultimately establish Greenwich, England, as the world's zero-degree longitude location, the "prime meridian."

Nevil Maskelyne's 1763 The British Mariner's Guide—and his follow-up The Nautical Almanac and Astronomical Ephemeris, published annually beginning in 1766—would set the standard for nautical navigation for decades to come.

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