"...Galileo had designed a special navigation helmet for finding longitude with the Jovian satellites. The headgear—the —has been compared to a brass gas mask in appearance, with a telescope attached to one of the eyeholes."
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Celatone — A device invented by Galileo Galilei to observe Jupiter s moons with the purpose of finding longitude on Earth. It took the form of a piece of headgear with a telescope taking the place of an eyehole. See also * Longitude prizeReferences* … Wikipedia
History of longitude — The history of longitude is a record of the effort, by navigators and scientists over several centuries, to discover a means of determining longitude. The measurement of longitude is important to both cartography and navigation. Historically, the … Wikipedia
Longitude prize — The Longitude Prize was a reward offered by the British government through an Act of Parliament in 1714 for a simple and practical method for the precise determination of a ship s longitude. The prize was administered by the Board of… … Wikipedia
