sextants
Celestial navigation instruments
Sextants are navigational instruments used to measure the angle between a celestial body and the horizon, allowing sailors and aviators to determine their position.
The device has a graduated arc of sixty degrees—one-sixth of a circle, hence the name.
Before GPS, sextants were essential for ocean navigation: The captain took a reading with his sextant at noon.
Traveling through unknown regions
- Age of SailEra of wind-propelled ships
- discoveryAct of finding something
- expeditionOrganized exploratory journey
- HadleyTropical atmospheric cell
octant · astrolabe · cross-staff · quadrant · Harrison · Endeavour · Magellan · circumnavigation
Of the sky above
- altitudeMeasured height above reference
- horizonApparent earth-sky meeting
- latitudeGeographic or personal freedom
- longitudeEast-west angular distance
position · bearing · dead reckoning · compass · chart · plotting · course · fix
Luminous celestial bodies
- PolarisCelestial north marker
- sunEarth's primary star
- moonNatural planetary satellite
- planetsStar-orbiting celestial bodies
celestial sphere · zenith · nadir · equinox · solstice · ecliptic · observation · magnitude
exploration
Traveling through unknown regions
- Age of SailEra of wind-propelled ships
- discoveryAct of finding something
- expeditionOrganized exploratory journey
Hadley · octant · astrolabe · cross-staff · quadrant · Harrison · Endeavour · Magellan · circumnavigation · cartography
celestial
Of the sky above
- altitudeMeasured height above reference
- horizonApparent earth-sky meeting
- latitudeGeographic or personal freedom
longitude · position · bearing · dead reckoning · compass · chart · plotting · course · fix · meridian
stars
Luminous celestial bodies
planets · celestial sphere · zenith · nadir · equinox · solstice · ecliptic · observation · magnitude · Sirius
arc
Curved line segment
- mirrorsReflective glass surfaces
- telescopeInstrument magnifying faraway objects
- vernierAuxiliary scale for fractions
graduations · drum · shades · frame · brass · ebony · limb · optics · eyepiece · filters
captain
One who commands
- navigatorRoute-directing crew member
- bridgeStructure spanning an obstacle
- shipSeagoing transport vessel
vessel · voyage · ocean · sailor · quartermaster · deck · chronometer · almanac · logbook · watch
- maritimeships, ship, boat, boats, anchors
- Age of ExplorationColumbus, Marco Polo, exploration, explorers, expeditions
- maritime historysailors, ships, seamen, sailing ships, celestial navigation
- seafaringship, sailors, ships, sail, sailor
- naval equipmentaircraft carrier, aircraft carriers, carriers, battleship, battleships
- Pacific MaritimeCaptain Cook, HMS Bounty, Bounty, mutiny, whaling
sextantsGPS
Satellite-based location technology
GPS receivers · satellite navigation · satellite navigation systems · radar · LORAN