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History of longitude

The history of longitude describes the centuries-long effort by astronomers, cartographers and navigators to discover a means of determining the longitude (the east-west position) of any given place on Earth. The measurement of longitude is important to both cartography and navigation. In particular, for safe ocean navigation, knowledge of both latitude…

Art & Measurement

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Longitude before the telescope

EratosthenesAlexandriaRhodesHipparchusPtolemy
35 related topics

Methods of determining longitude

Magnetic declinationSextantRegiomontanusAmerigo VespucciJohannes Werner
40 related topics

Government initiatives

Philip II of SpainPhilip IIIDucatsFlorinsParis Observatory
25 related topics

Land surveying and telegraphy

Nathaniel BowditchState HouseBostonPittsfieldUnited States Coast and Geodetic Survey
43 related topics

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Overview

Longitude before the telescope

Telescopes and clocks

Methods of determining longitude

Land and sea

Government initiatives

Lunar distances versus chronometers

Land surveying and telegraphy

Wireless methods

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History of longitude

Nodes209
Edges208
Triples5
Avg. degree1.99
Density0.009569
Components1

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Important terminology

longitude time method chronometers used lunar observations first made accurate accuracy sea clocks two astronomical could distances use determining century

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
David Thompsoninstance ofand lunar distances were the main method used by surveyors0.80text
Thomas Earnshawinstance ofOther makers0.80text
who developed the spring detent escapementinstance ofOther makers0.80text
simplified chronometer designinstance ofOther makers0.80text
productioninstance ofOther makers0.80text

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