Board of Longitude chronometers, keeping) the time of the reference place when one is far away from it. For details of the efforts towards determining the longitude, see History of longitude. For many decades a sufficiently accurate chronometer was prohibitively expensive. The lunar distance method was used by mariners either in conjunction with or instead of the marine chronometer. However, with the expectation that accurate clocks would eventually become commonplace, John Harrison showed that his method was the way of the future. However the board, to its discredit, never awarded the prize to Harrison, nor anyone else. With the significant problems considered as
History of longitude European and North American longitude measurement campaigns in the 1850s and 1860s, resulting in improved map accuracy and navigation safety. Synchronization by radio followed in the early 20th century. In the 1970s, the use of satellites was developed to more precisely measure geographic coordinates (GPS). In the process of searching for a solution to the problem of determining longitude, many scientists added to the knowledge of astronomy and physics. History of longitude The history of longitude is a record of the effort, by astronomers, cartographers and navigators over several centuries, to discover a means of determining longitude. The measurement of