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Bathymetry
Bathymetry is like creating a 3D map of the ocean floor. Just like a map shows mountains and valleys on land, bathymetry shows us the hills and trenches beneath the waves.
Chronometer
A precision timekeeping device crucial for determining longitude by comparing the local time to a known reference time.
Data
Information collected during surveys, used to create maps and charts.
Dead reckoning
A method of estimating a ship's position based on previously determined positions, and advancing that position based on known or estimated speeds over elapsed time, along with the direction of travel.
GNSS (Global Navigation Satellite System)
A broader term for satellite navigation systems that provide autonomous geo-spatial positioning with global coverage.
GPS (Global Positioning System)
A satellite-based system that provides precise location and time information anywhere on Earth.
Hydrographic survey software
Computer programmes used to process, interpret, and visualize data collected during hydrographic surveys, transforming raw data into comprehensible maps and charts of the underwater world.
Hydrography
The science of mapping and understanding the physical features of water bodies and their surroundings.
Inertial navigation technology
A type of navigation that uses motion sensors (accelerometers) and rotation sensors (gyroscopes) to continuously calculate by dead reckoning the position, orientation, and velocity of an object without the need for external references.
Mapping
The process of creating maps, which involves the collection, analysis, and presentation of geographical data.
ROVs (Remotely Operated Vehicles)
Unmanned submarines controlled remotely, used for exploring underwater environments too tight or dangerous for human divers.
Lead line
A tool for measuring the depth of water by dropping a weighted line and measuring the length of the line that reaches the bottom.
Multi-beam echo sounders
Advanced systems that emit multiple sound beams simultaneously to map a wider area of the seafloor, offering a detailed view of its topography.
Nautical charts
Detailed maps used for navigation on the water, showing depths, hazards, and other important features.
Polynesian navigators
Ancient mariners of the Pacific Ocean who mastered the art of navigating vast distances without modern instruments, relying instead on natural cues.
Sextant
A navigational instrument used to measure the angle between celestial objects and the horizon, aiding in determining latitude.
Single-beam echo sounders
Devices that use a single sound pulse to measure the depth directly beneath them, providing precise but narrow coverage of the seafloor.
Sonar
A technology that uses sound waves to detect and measure distances underwater.
Star navigation
The technique of using stars and constellations as guides for determining one's position and direction while at sea.
Stick charts
Navigational maps made from sticks and shells, representing ocean swells, currents, and island locations, used by Polynesian navigators.
Wayfinding
The traditional Polynesian method of navigation using environmental signs, including the stars, ocean swells, wind patterns, and the behaviour of birds.
