View source for Marine navigation

{{Short description|Process of steering a ship from a starting point to a destination}}
{{more citations needed|date=January 2023}}

[[File:Table_of_Geography_and_Hydrography,_Cyclopaedia,_Volume_1.jpg|thumb|301x301px|Table of geography, hydrography and navigation, from the [[Cyclopædia, or an Universal Dictionary of Arts and Sciences|Cyclopaedia]] of 1728.]]
'''Marine [[navigation]]''' is the art and science of steering a [[ship]] from a starting point (sailing) to a destination, efficiently and responsibly. It is an [[art]] because of the [[skill]] that the navigator must have to avoid the dangers of navigation, and it is a [[science]] because it is based on [[physics|physical]], [[mathematical]], [[oceanographic]], [[cartographic]], [[astronomical]], and other knowledge.

Marine navigation can be surface or [[Submarine navigation|submarine]].

== Etymology ==
Navigation (from the [[Latin]] word ''navigatio'') is the act of sailing or voyaging. Nautical (from Latin ''nautĭca'', and this from [[Greek language|Greek]] ναυτική [τέχνη] ''nautikḗ [téjne]'' "[art of] sailing" and from ναύτης ''nautes'' "sailor") is that pertaining to navigation and the science and art of sailing. Naval (from the Latin adjective ''navalis'') is that relating to ships and navigation, or particularly to the [[navy]].<ref>[[wiktionary:Navigation|Navigation]]: theory and practice of charting a course for a ship, aircraft or spaceship. [[wiktionary:nautical|Nautical]]: Relating to or involving ships or shipping or navigation or seamen. [[wiktionary:naval|Naval]]: (''nautical'') Of or relating to ships in general.</ref>

In [[Ancient Rome]], the ''navicularii'' conducted long-distance trade by sea.

== History ==
[[Cabotage|Coastal navigation]] was practiced since the most ancient times.<ref>{{Cite web |title=15.1 The Earliest Ships and Sailors — The Outline of History by H. G. Wells |url=https://outline-of-history.mindvessel.net/150-sea-peoples-and-trading-peoples/151-the-earliest-ships-and-sailors.html |access-date=2023-01-20 |website=outline-of-history.mindvessel.net}}</ref> The biblical account of [[Flood myth|the great flood]], where the [[Noah's Ark]] appears, is based both on myths and on the navigational practice of the [[Mesopotamia|Mesopotamian civilizations]], who from the [[Sumerians]] onwards navigated their two rivers ([[Tigris]] and [[Euphrates]]) and the [[Persian Gulf]]. The [[ancient Egypt]]ians did not limit themselves to [[inland navigation]] of the [[Nile]] either, and used the [[Mediterranean Sea|Mediterranean sea]] routes existing since the [[Neolithic]] — through which cultural phenomena such as [[megalith]]ism or the [[Metallurgy#History of metallurgy|metallurgy]] would have [[Trans-cultural diffusion|spread]] for millennia. The [[Crete|Cretans]] even established a true ''[[thalassocracy]]'' (government of the seas, attributed to King [[Minos]]) until the [[Mycenaean Greece|Mycenaean period]] (2nd millennium BC), when the events mythologized in the [[Homer|Homeric poems]]<ref group="Note">More than a thousand "concave ships" [[Trojan War|arriving on the beaches of Troy]], bad fortune of the navigator [[Odysseus|Ulysses]] and the expertise of the "[[Argonauts]]" — among whom is the builder of the ship that bears his name, [[Argus (Argonaut)|Argus]]</ref> ought to be placed.{{wide image|AKROTIRI SHIP-PROCESSION-FULL PANO-3.jpg|1500px|Fresco from the Western House of [[Akrotiri (prehistoric city)|Akrotiri]], called ''flotilla'' or "procession of boats".}}The [[Hittites]], led by King [[Šuppiluliuma II]] faced the [[Cyprus]] in the first historically recorded [[Naval warfare|naval battle]] (ca. 1210 BC); at the same time, all the civilizations of the [[Eastern Mediterranean]] suffered from the incursions of the denominated "[[Sea Peoples]]".

The [[Phoenicia]]ns — whom the [[Culture of Greece|Greeks]] considered their masters in navigation and who are also cited in the Bible —<ref group="Note">Ships from [[Tyre, Lebanon|Tyre]] supplied King [[Solomon]] with goods from distant places, including ''Tarshish'' — [[Tartessos]] — to the same destination a Phoenician ship was carrying [[Jonah]], until the crew threw him into the sea when they blamed him for the storm that threatened to sink them.</ref><ref>{{Cite web |title=New Perspectives on Phoenician Sailing |url=http://www.metmuseum.org/exhibitions/listings/2014/assyria-to-iberia/blog/posts/phoenician-sailing |access-date=2023-01-20 |website=www.metmuseum.org}}</ref> would have been the first Mediterranean civilization to sail [[Pedro de Medina|the high seas]] by [[sculling]] and [[sailing]], guided by the sun during the day and by the [[Polaris|North Star]] at night. It is recorded that, crossing the [[Strait of Gibraltar]] — the "Rock of Gibraltar", the so-called "[[Pillars of Hercules]]" in the Greek myths — they sailed across the [[Atlantic Ocean]] reaching the south to some point on the west coast of Africa and the north to the [[British Isles]] (or even beyond, to the place that the texts call [[Thule]]), but it is unclear if they circumnavigated Africa or crossed the Atlantic reaching America, something most likely achieved by [[Norse colonization of North America|the Norsemen]] in the 10th century.
[[File:Predynastic_boat_vase_opt451x456_Edgerton-1927_AJSLp121-c.jpg|thumb|Boat depicted on Egyptian pottery from the Predynastic period (Naqada II, mid-4th millennium BC).]]
[[File:Barque_Solaire.JPG|thumb|[[Khufu ship]], IV dynasty, ca. 2500 BC.]]
[[File:Saqqara_BW_11_c.jpg|thumb|Boat building depicted in reliefs from the [[Mastaba of Ti]] at Saqqara, dynasty V, mid-3rd millennium BC.]]
[[File:Maler_der_Grabkammer_des_Menna_013.jpg|thumb|Egyptian boat represented in the [[TT69|tomb of Menna]], [[List of Theban tombs|Tombs of the Nobles]], 18th dynasty, mid-2nd millennium BC.]]
[[File:Antico_regno,_modello_di_nave,_da_saqqara,_01.JPG|thumb|Model of an Egyptian ship and crew.]]
[[File:Woodtrade.jpg|thumb|Type of Phoenician ships called ''[[Hippos (Golan Heights)|hippos]]'' (name given by the Greeks, because of its [[Mascaron (architecture)|mascaron]] shaped like a horse's head) carrying wood, depicted in an [[Assyrian sculpture|Assyrian relief]] from Sargon's palace at [[Dur-Sharrukin|Khorsabad]].]]
[[File:AssyrianWarship.jpg|thumb|King Luli of [[Sidon]] flees from his city, attacked by [[Sargon II]], in a type of Phoenician warship called ''dieris'' ([[bireme]], with two rows of rowers). [[Assyrian sculpture|Assyrian relief]] from the palace of [[Sennacherib]], ca. 700-692 BC.]]
[[File:MazarronIIg.jpg|thumb|One of the [[Phoenician vessels of Mazarrón]], 7th century BC.]]
[[File:Exekias_Dionysos_Staatliche_Antikensammlungen_2044_n2.jpg|thumb|Dionysus Cup, by [[Exekias]], 6th Century]]
[[File:Odysseus_Sirens_BM_E440_n2.jpg|thumb|Scene from the ''[[Odyssey]]'' (Ulysses' companions manage to free their ship from the Sirens' trap, while their leader listens to their song tied to the mast). 5th century.]]
[[File:Fresco Isis Giminiana Musei Vaticani (inv, 79638).jpg|thumb|Roman ship represented in a fresco of the 2nd or 3rd century in the port city of [[Ostia Antica|Ostia]]. The inscriptions reflect the name of the ship (Isis Giminiana), the name of the captain or ''magister'' (Farnaces, at the helm) and the name of the owner (Arascanius, in charge of the cargo).<ref>{{cite web |title=The Rome 101 blog |url=https://rome101.com/2013/12/ |archive-url=https://web.archive.org/web/20161120012119/https://rome101.com/2013/12/ |archive-date=20 November 2016 |access-date=19 November 2016}}</ref>]]
[[File:Museum_für_Antike_Schifffahrt,_Mainz_01._Spritsail.jpg|thumb|Roman sarcophagus from the 3rd century. It is the oldest representation of a [[spritsail]].]]
[[File:Byzantine_ships_-_Harbor_of_Classe_mosaic_-_Sant'Apollinare_Nuovo_-_Ravenna_2016.jpg|thumb|Byzantine ships in Classe (the port of [[Ravenna]]), depicted in a mosaic of [[Basilica of Sant'Apollinare Nuovo]], 6th century.]]
[[File:Le_bateau_viking_dOseberg_(4835828216).jpg|thumb|[[Oseberg Ship]], 9th century.]]
[[File:Tapisserie_bato1.jpg|thumb|Norman ship represented in the [[Bayeux tapestry]], 11th century.]]
[[File:Wikinger.jpg|thumb|[[Longship#Types of longships|Viking ships]] depicted in a 12th-century manuscript.]]
[[File:Greekfire-madridskylitzes1.jpg|thumb|Nautical combat with [[Greek fire]] depicted in a 12th-century Byzantine manuscript (''[[Madrid Skylitzes]]'').]]
[[File:Fànos.jpg|thumb|Scene of [[Fishing light attractor|lamp fishing]]]]
[[File:Faluca_Almariya_02.jpg|thumb|Replica of a Spanish-Muslim ship from the 10th to 14th century.]]
[[File:Galley.jpg|thumb|[[Galley]] or ''[[dromon]]'' in a Byzantine fresco from the 13th century. The design of the flags is similar to the [[Senyera]] of the Crown of Aragon, and the design of the ship can be compared to the traditional mitjana ship.]]
[[File:Medieval_ship_and_compass_(Mandeville).jpg|thumb|The earliest known representation of a compass, used aboard ship, depicted in an illustration dated 1403.]]
<gallery mode="packed">

File:Musée de l'Arles antique, Arles, France (16006774188).jpg|Remains of a 1st-century Gallo-Roman ship archaeologically named ''[[Arles Rhône 3]]''.

File:Dictionary of Roman Coins.1889 P381S0 illus385.gif|Roman ship depicted on a coin.

File:Phoenician ship.jpg|Relief of a 2nd-century sarcophagus representing a "gauloi", a trading ship.

File:Bait Al Baranda Museum-Naval battle.JPG|Model depicting a naval confrontation between a Roman ship and Omani ships in the Indian Ocean, 2nd century.

</gallery>In the [[Indian Ocean|Indian]] and [[Pacific Ocean|Pacific]] oceans, the oceanic navigations made it possible to populate all the archipelagoes ([[Polynesian navigation]]). However, the possibility of [[Kon-Tiki expedition|reaching South America]] is still a matter of debate — the [[settlement of the Americas]] through the [[Bering Strait]] would not have required navigation, or in any case, coastal navigation would have sufficed — as well as other possible [[Pre-Columbian trans-oceanic contact theories|pre-Columbian transoceanic contacts]]. In the first quarter of the 15th century, the Chinese expeditions led by [[Zheng He]] reached the African coasts of the Indian Ocean. It has been [[Gavin Menzies#1421: The Year China Discovered the World|proposed]] that they might have reached the South Atlantic and even America and Europe, but this proposal has not been accepted beyond mere speculation.{{wide image|Mokoshuraiekotoba.jpg|700px|Naval combat between [[Junk (ship)|Chinese junks]] employed in the foiled [[Mongol invasions of Japan]], and ''samurai'' defenders, ca. 1293.}}Mediterranean navigation, which the Romans had come to control (undisputed ''[[Mare Nostrum]]'' since their victories over the Carthaginians in the [[Punic Wars]] [264-146 BC], the Egyptians during the [[Battle of Actium]] [31 BC], and [[Piracy|pirates]]), was once again a contested environment in the [[Middle Ages]], from the moment the [[Vandals]] managed to attack the Italian coasts from the sea. In the 6th century, the [[Byzantine Empire|Byzantines]] managed to regain control, and in the 7th century it was the [[Arab world|Arabs]] who ended up dividing the [[Mediterranean Basin|Mediterranean area]],<ref>{{Cite journal |last=Pirenne |first=Henri |date=1922 |title=Mahomet et Charlemagne |url=https://fr.wikisource.org/wiki/Mahomet_et_Charlemagne |journal=Revue belge de philologie et d'histoire |volume=1 |pages=77–86|doi=10.3406/rbph.1922.6157 }}</ref> which even the [[Vikings]] and [[Normans]] were able to access. Since the time of the [[Crusades]], [[Republic of Venice|Venetian]],<ref>[[Venetian navy]]</ref> [[Republic of Genoa|Genoese]]<ref>[[Genoese navy]]</ref> and [[Crown of Aragon]]<ref>{{Cite journal |last=Salabert |first=Vicente |date=1970–1971 |title=La expansión catalano-aragonesa por el Mediterráneo en el siglo XIV |journal=Anuario de Estudios Medievales |language=es |issue=7 |issn=0066-5061}}</ref> navigators also had a strong presence. Knowledge of the [[compass]], transmitted to the Europeans by the Arabs (who in turn had obtained it from the Chinese), together with other improvements in astronomical techniques ([[astrolabe]], [[Jacob's staff]], [[sextant]], cartographic techniques ([[Portolan chart|portulan]] and shipbuilding ([[caravel]], [[Nau (ship)|nau]], [[galleon]]), made the [[Age of Discovery]] — initially led by the [[Portuguese people|Portuguese]] and [[Castilians]] — possible, especially after [[Prince Henry the Navigator|Henry the Navigator]] impulsed the [[Sagres school|school of Sagres]]. In 1492, the [[Voyages of Christopher Columbus#First voyage (1492–1493)|first voyage of Christopher Columbus]] took place. In 1488, [[Bartolomeu Dias]] rounded the [[Cape of Good Hope]], which [[Portuguese discovery of the sea route to India|opened the route to the Indian Ocean]] — [[Vasco da Gama|Vasco de Gama]] reached Calicut (India) in 1498. Between 1519 and 1521, the [[Magellan expedition|Magellan-Elcano expedition]] circumnavigated the world — measuring the [[Longitude|geographical longitude]] with the method of its scientific organizer, [[Rui Faleiro]]. Until the 6th century, the Spanish-Portuguese hegemony in navigation was patent in fields such as geography and [[cosmography]]. Both English and French pilots learned to navigate from the texts of [[Pedro de Medina]], [[Martín Fernández de Enciso]] and [[Martín Cortés, 2nd Marquess of the Valley of Oaxaca|Martín Cortés]], among others.<ref>{{Cite book |last=Picatoste |first=Felipe |title=Apuntes para una biblioteca científica española del Siglo XVI: estudios biográficos y bibliográficos de ciencias exactas físicas y naturales y sus inmediatas aplicaciones en dicho siglo |year=1891 |language=es}}</ref><ref name="ref_duplicada_1">''Diccionario enciclopédico popular ilustrado Salvat'' (1906-1914)</ref> The conjunction of "cannons and sails" has been argued to have given European states the advantage to prevail over the rest,<ref>Cipolla, Carlo Maria, ''Cañones y velas en la primera fase de la expansión europea'', 1967.</ref> launching the modern "[[World-systems theory|world system]]".<ref>Fernand Braudel, Immanuel Wallenstein.</ref><gallery mode="packed">

File:The Four Voyages of Columbus 1492-1503 - Project Gutenberg etext 18571.jpg|Navigation of Columbus' four [[Christopher Columbus#Voyages|voyages]] to America, 1492–1504.

File:Gama route 1.svg|Navigation of [[Vasco de Gama]] first voyage, 1498.

File:Detail from a map of Ortelius - Magellan's ship Victoria.png|The [[Victoria (ship)|''Victoria'']], ship of the [[Magellan expedition|Magellan-Elcano expedition]] (1519-1521), in an illustration of a map by [[Abraham Ortelius]], 1590.

File:Museo Marítim de Barcelona Real 17-05-2009 13-09-59.JPG|Model of the galley ''[[Real (galley)|Real]]'', flagship of the Christian navy in the [[Battle of Lepanto]] (1571).

File:Vroom Hendrick Cornelisz Battle of Haarlemmermeer.jpg|Dutch ''gueux de mer'' engage the Spanish at the [[battle of Haarlemmermeer]], 1573; painting by [[Hendrick Cornelisz Vroom]], ca. 1621.

File:Boazio-Sir Francis Drake in Santo Domingo.jpg|[[Francis Drake]]'s fleet in front of [[Santo Domingo]] in 1585.

File:Routes of the Spanish Armada-es.svg|Navigation of the [[Spanish Armada]], 1588.

</gallery>{{wide image|La sevilla del sigloXVI.jpg|700px|''[[View of Seville]]'', attributed to [[Alonso Sánchez Coello]] (ca. 1576-1600).<ref>{{Cite web |title=Red Digital de Colecciones de Museos de España - Museos |url=http://ceres.mcu.es/pages/ResultSearch?Museo=MAM&txtSimpleSearch=Vista%20de%20Sevilla&simpleSearch=0&hipertextSearch=1&search=simple&MuseumsSearch=MAM%7C&MuseumsRolSearch=11&%20Ficha%20en%20Ceres-Ministerio%20de%20Cultura-Museo%20de%20Am%C3%A9rica |access-date=2023-01-19 |website=ceres.mcu.es |language=es}}</ref>}}{{wide image|16th century Portuguese Spanish trade routes.png|700px|Permanent navigation routes of the Spanish (in white) and Portuguese (in blue) fleets since the 16th century. The [[Spanish treasure fleet]] crossed the Atlantic, the [[Manila Galleon]] the Pacific; the India armada circumnavigated Africa.}}<gallery mode="packed">

File:The conquest of the great Northwest; being the story of the Adventurers of England known as The Hudson's Bay Company. New pages in the history of the Canadian Northwest and Western States (1908) (14778654772).jpg|Navigation of [[Henry Hudson]] in search of the [[Northeast Passage]], 1607–1608.

File:Wasa, Seitenansicht.jpg|''[[Vasa (ship)|Vasa]]'', flagship of the Swedish navy, sunk on her maiden voyage, 1628.

File:AMH-6135-NA View of Batavia.jpg|Dutch ships of the [[Dutch East India Company|VOC]] (''Vereenigde Oostindische Compagnie'', ''United East India Company'') in Batavia (today [[Jakarta]]), 1665.</gallery>Since the 18th century, England exercised maritime hegemony, a fact that was confirmed in the early 19th century with the [[Battle of Trafalgar]] (1805). Among the main English expeditions of the time were [[James Cook|Captain Cook]]'s (1768-1779), also the second expedition of the [[HMS Beagle|Beagle]] (1831-1836) — which was of great importance for the later development of [[Charles Darwin]]'s [[Evolution|theory of evolution]]. Already fully in the age of [[steam navigation]], techniques and vessels continued to be perfected in transoceanic sailing ([[clipper]]), that did not become obsolete for commercial navigation until the 20th century — especially after the opening of the [[Panama Canal]]. Even then, the unbridled optimism that characterized the naval design of the time suffered a severe blow with the sinking of the [[Sinking of the Titanic|Titanic]] (1912).<gallery mode="packed">

File:"Toma" de Cartagena por Vernon.jpg|Medal used by the British navy to celebrate [[Battle of Cartagena de Indias|the capture of Cartagena de Indias]], that did not take place (1741).

File:Endeavour, Thomas Luny 1768.jpg|''[[HMS Endeavour|Endeavour]]'' (Captain Cook's ship) leaves [[Whitby]] harbor in 1768.

File:Francesco Guardi - The Doge on the Bucentaur at San Niccolò del Lido - WGA10850.jpg|Venetian ships (including the ''[[Bucentaur]]'') at the feast of the Ascension, painting by [[Francesco Guardi]], ca. 1775.

File:Expédition de La Pérouse.jpg|Expedition of Jean-François de [[Jean-François de Galaup, comte de Lapérouse|La Perouse]], 1785–1788.

File:Slaveshipplan.jpg|Arrangement of a [[slave ship]] for the [[Slavery|slave trade]] in 1788. The [[triangular trade]] crossing the Atlantic between Europe, Africa and America constituted the most important shipping routes at the time.

File:Descubiertaatrevida.jpg|The ''Descubierta'' and the ''Atrevida'' in the Philippine island of Samar, during the [[Malaspina expedition]], 1789–1794.

File:Real Expedición Filantrópica de la Vacuna 01.svg|Navigations of the [[Balmis Expedition|Royal Philanthropic Vaccine Expedition]], 1803–1814.

File:Turner, J. M. W. - The Fighting Téméraire tugged to her last Berth to be broken.jpg|''[[The Fighting Temeraire]] tugged to her last berth to be broken up'', by [[J. M. W. Turner]], 1838.

File:London and the River Thames seen from the south, from Wellcome L0023697.jpg|Active navigation on the [[Thames]] in the mid-19th century, in an engraving by Frederick James Smyth. Tall-masted ships crowd downstream, while barges and steamboats with smoking smokestacks are allowed to cross [[London Bridge]].

File:Jack Spurling - ARIEL & TAEPING, China Tea Clippers Race.jpg|The "Ariel" and the "Taeping" contesting the ''Great Tea Race of 1866'', depicted in a painting by Jack Spurling.

File:The destruction of Russian destroyers by Japanese destroyers at Port Arthur.jpg|Naval engagement between Russian and Japanese destroyers at [[Lüshunkou District|Port Arthur]] during the [[Russo-Japanese War]], 1904.

File:Aan de Zuidpool - p1913-164-1.jpg|[[Roald Amundsen|Amundsen]] expedition to the South Pole, 1913.

File:Stöwer U-Boot Truppentransporter.jpg|Sinking of an enemy ship by a German "[[U-boat]]" in 1917. In addition to [[submarine warfare]], [[Submarine|submersible vessels]] have had all sorts of uses, including [[mail]],<ref>{{Cite web |title=Correo submarino - Marinos Mercantes |url=http://www.webmar.com/foros/viewtopic.php?f=43&t=4991%20%27%27Correo%20submarino%27%27,%20en%20Marinos%20Mercantes |access-date=2023-01-19 |website=www.webmar.com}}</ref> the [[oceanography]] or [[polar exploration]].<ref>{{Cite news |date=2007-08-02 |title=Rusia planta su bandera en el Ártico |language=es |url=http://news.bbc.co.uk/hi/spanish/international/newsid_6927000/6927179.stm |access-date=2023-01-19}}</ref>

File:The Royal Navy during the Second World War- Operation Overlord (the Normandy Landings)- D-day 6 June 1944 A24096.jpg|The [[Operation Overlord]] (June 1944) was the largest naval operation in history, in a relatively small maritime environment (the [[English Channel]]).

File:USS Flint (CL-97) at anchor in March 1945 (80-G-K-3813).jpg|The [[United States Fifth Fleet]] departs for Okinawa in March 1945, in the final stages of the [[War of the Pacific]].

</gallery>Contemporary shipping has massively ceased to perform one of its traditional functions and has been replaced by aviation, such as [[Transport|passenger transport]], although with two important exceptions: leisure travel ([[tourism]] by [[cruise ship]]s) and irregular traffic of people ([[Illegal immigration|irregular immigration]]). Since the [[Second Industrial Revolution]], the main volume of [[freight transport]] has been hydrocarbons ([[oil tanker]]s and [[Gas carrier|gas tankers]]). Other raw materials are also transported in [[Bulk cargo|bulk]] on [[cargo ship]]s, but from 1956 onward, a large part of goods of all kinds were adapted to standardized [[container]]s that speed up loading and unloading, allowing a combination with land transport ([[Transport hub|hub]]). Highly technological navigation has reduced crews and increased the size of ships. For example, in [[Fishing|deep-sea fishing]], which locates its prey with sophisticated means and lasts indefinitely in time — freezer ships or [[factory ship]]s — which in some circumstances has made them vulnerable to new forms of piracy.<gallery mode="packed">

File:Calypso51-73.jpg|Routes of the ''[[RV Calypso|Calypso]]'', research ship of [[Jacques Cousteau|Commander Cousteau]].

File:Port Havre 2.jpg|Cargo vessel using the appropriate facilities for container traffic ([[container crane]]s) at the port of [[Le Havre]].

File:Cayuco approached by a spanish Salvamar vessel.jpg|Boat overloaded with illegal immigrants, alongside a Spanish [[coast guard]].

</gallery>{{wide image|Hellespont_Alhambra-223713_v2.jpg|500px|''Hellespont Alhambra'', a TI-class supertanker that is considered among the largest ships in the world in dimensions, displacement and cargo capacity.}}

== Methods and techniques ==
These are the methods used in maritime navigation to solve the three problems of the navigator:

* Determining and maintaining the "course".

* Determining the "time", the "speed" and "distance", for the duration of the voyage.

* Knowing the "depth" in which one is sailing so as not to run aground.

=== Coastal navigation ===
Navigation and location of the ship by positioning techniques based on the observation of [[Bearing (angle)|bearings]] and distances to notable points on the coast ([[lighthouse]]s, [[Cape (geography)|capes]], [[buoy]]s, etc.) by visual means ([[Pelorus (instrument)|pelorus]]), observation of horizontal angles ([[sextant]]) or electronic methods (bearings from [[radar]] to [[Radar beacon|racons]], [[transponder]]s, etc.)

=== Dead reckoning navigation ===
{{See also|Dead reckoning}}
Navigation and location of the ship by analytical means, after considering the following elements: initial location, [[Bearing (angle)|bearing]](s) — whether [[Bearing (angle)#Absolute|absolute bearings]], surface bearings, or [[Bearing (angle)#Relative|relative bearings]]. Also [[velocity]] as well as the external factors that have influenced the course either partially or entirely, such as the [[wind]] ([[leeway]]) and/or the [[Ocean current|current]] (bearing of the current and hourly current intensity). The point obtained from the calculations is called the "Dead reckoning location", with its corresponding [[latitude]] and [[longitude]]. This point is also known as Fantasy point.

=== Loxodromic navigation ===
[[File:Loxodrome.png|thumb|Rhumb line navigation path: β = constant]]
{{Main|Loxodromic navigation}}
Navigation that follows a [[rhumb line]] — that is, all meridians are cut at the same angle. On a [[nautical chart]] following the [[Mercator projection]], a loxodromic is represented by a straight line.

This type of navigation is useful for not too long distances, as it allows the course to remain steady,<ref name="WeintritNeumann2011">{{cite book |first1=Adam |last1=Weintrit |url=https://books.google.com/books?id=buMsPGyE7boC&q=loxodromic+navigation&pg=PA139 |title=Methods and Algorithms in Navigation: Marine Navigation and Safety of Sea Transportation |first2=Tomasz |last2=Neumann |date=7 June 2011 |publisher=CRC Press |isbn=978-0-415-69114-7 |pages=139–}}</ref> but it does not offer the shortest distance.

=== Orthodromic navigation ===
{{Main|Great-circle navigation}}
Navigation that follows the shortest distance between two points, i.e., that which follows a [[great circle]]. Such routes yield the shortest [[distance]] between two points on the globe.<ref name="WeintritNeumann2011" /> To calculate the bearing and distance between two points it is necessary to solve a [[Spherical trigonometry|spherical triangle]] whose vertices are the origin, the destination, and the pole.<ref>{{Cite web |date=2009-04-22 |title=Navisfera de Wilson |url=http://br.geocities.com/simaowilson/navisfera.html |access-date=2023-01-24 |archive-url=https://web.archive.org/web/20090422184846/http://br.geocities.com/simaowilson/navisfera.html |archive-date=2009-04-22 }}</ref>

=== Celestial navigation ===
{{Main|Celestial navigation}}
Navigation and location of the ship by [[geopositioning]] techniques based on the observation of the [[star]]s and other [[Astronomical object|celestial bodies]]. The variables measured to find the location are: the observed angular height of the stars above the [[horizon]], measured with the [[sextant]] (formerly with the [[astrolabe]] or other instrument), and the [[time]], measured with the [[Clock|chronometer]].

Conceptually, the process is not complex to understand:

* Knowing the time of the observation, and with the data contained in the nautical calendar, it is possible to determine the astronomical coordinates of the observed star.

* Knowing the coordinates of the observed star and the height above the horizon with which it was observed, we can deduce that the observer's position is located on a circle whose center is located at the geographical point directly below the star.

* Any observer located at any point on that circle will observe the star with the same height above the horizon.

* The observer can therefore know that his position is somewhere on this circle.

In practice, the mathematical process, called "reduction" of the observation, can be complex for the uninitiated. To the height observed with the sextant, it is necessary to apply a series of corrections to compensate for atmospheric refraction, [[parallax]] and other errors. Once this is done, it is necessary to solve a [[Spherical trigonometry|spherical triangle]] by mathematical and trigonometric methods.

There are many methods to do this. The manual methods use tables ([[Trigonometry|trigonometric]], [[logarithm]]s, etc.) to facilitate the calculations. The introduction of [[calculator]]s and [[Computer|electronic computers]] at the end of the 20th century greatly facilitated the calculation, but the creation of [[Global Positioning System|GPS]] made celestial navigation no longer important, relegating it to the background as an alternative method in case of failure of the on-board electronics or as a hobby of scientific interest.

=== Electronic navigation ===
{{Main|Satellite navigation}}
Navigation and location of the ship by positioning techniques based on the aids provided by global positioning systems, such as [[Global Positioning System|GPS]], [[GLONASS]], or [[Galileo (satellite navigation)|GALILEO]]. It is the system most widely spread and easiest to use, in spite of the errors that may arise.

=== Inertial navigation ===
{{Main|Inertial navigation system}}
Navigation and location of the ship by means of the analysis of the data provided by [[accelerometer]]s and/or [[gyroscope]]s located on board, which integrate the accelerations experienced in complex electronic systems, that converted into velocities (in the 3 possible axes of displacement) and according to the observed courses, make it possible to obtain the location of the ship.

== Iconography ==
The harbinger of a successful navigation was the [[dolphin]], which is why its representation became the symbol carried by all ships.

More recently, navigation was represented as a woman crowned with [[Stern|ship's sterns]] whose clothes are agitated by the winds. She rests one hand on a rudder and the other holds the instrument for measuring height. At her feet, the [[ampoule]], the compass, the [[trident]] of Neptune and the riches of commerce, while the sea can be seen on the horizon, completed by a lighthouse and traversed by ships at full sail.<ref name="ref_duplicada_1" />

== See also ==
* [[Age of Sail]]
* ''[[Bowditch's American Practical Navigator]]''
* [[Navigation]]
* [[Jimmy Cornell#World Cruising Routes|World Cruising Routes]]

== Notes ==
<references group="Note" />

== References ==
<references />

== External links ==
{{Commons|Navigation}}
{{wikiquote}}
{{Wikisource|Portal:Navigation}}
{{Wikivoyage}}

* {{ExternalLink|https://web.archive.org/web/20071101051158/http://www.geocities.com/alfgon.geo/cnhist-es.htm|Historia de la navegación astronómica}} {{in lang|es}}
* {{ExternalLink|https://web.archive.org/web/20050727082422/http://www.atna.com.ar/|Amigos de la tradición náutica argentina}} {{in lang|es}}
* {{ExternalLink|https://web.archive.org/web/20090422184846/http://br.geocities.com/simaowilson/navisfera.html|Esfera armilar, aplicada em navegação}} {{in lang|pt}}

{{Seamanship}}
{{Ancient seafaring}}

[[Category:Navigation]]
[[Category:Ships]]
[[Category:Celestial navigation]]
[[Category:Sailors]]