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23 results for "sonar contacts" — page 1 of 2
I_4_03 — USO Hotspots and Underwater Anomaly Zones
Unidentified Submerged Objects (USOs) — anomalous phenomena observed in or entering/exiting bodies of water — have been reported from specific geographic zones with particular concentration since the 1940s. The Catalina
ZF_5_02 — Sonar and Acoustic Ocean Sensing: Technology and Discovery
Sonar (SOund NAvigation and Ranging) is the primary technology for sensing the underwater environment — an acoustic analog to radar that exploits the fact that sound travels efficiently through water while electromagneti
ZB_1_07 — Echolocation: Biological Sonar in Bats, Dolphins, and Beyond
Echolocation — the ability to perceive the environment by emitting sounds and analyzing returning echoes — has evolved independently in bats, toothed whales (dolphins, porpoises, sperm whales), some birds (oilbirds, swif
ZF_4_17 — Anthropogenic Ocean Noise: Acoustic Pollution and Marine Life
Anthropogenic ocean noise — the introduction of human-generated sound into the marine environment — has increased dramatically since the mid-20th century, transforming the ocean soundscape from one dominated by biologica
M_5_04 — Submerged Structures of the Mediterranean — Pavlopetri to Baiae
The Mediterranean Sea contains some of the world's best-documented and most archaeologically significant submerged settlements and structures — sites that were built on dry land and subsequently inundated by combinations
M_2_08 — Underwater Structures of Lake Titicaca & Japan
Multiple significant underwater stone formations have been documented in two distant but thematically related regions: Lake Titicaca (Bolivia/Peru) and the waters surrounding the southern Japanese Ryukyu Islands.
ZF_2_03 — Marine Migration Patterns and Cetacean Intelligence
Marine animals execute some of the most extraordinary navigational feats in biology — humpback whales migrating 8,000+ km between polar feeding grounds and tropical breeding waters, sea turtles returning to their natal b
ZF_3_17 — Anthropogenic Ocean Noise Pollution
Anthropogenic ocean noise — sound from shipping, seismic surveys, military sonar, construction, and industrial activity — has increased ambient ocean sound levels by an estimated 32-fold (15 dB) in many ocean regions sin
ZF_3_04 — USOs: Unidentified Submerged Objects and Trans-Medium Phenomena
Unidentified Submerged Objects (USOs) — anomalous craft or phenomena observed entering, exiting, or operating beneath the ocean surface — represent one of the most intriguing and least explained categories of unidentifie
ZF_3_02 — Maritime Archaeology: Shipwrecks, Sunken Cities, and Submerged Structures
Maritime archaeology — the study of human interaction with the sea through material remains — has matured from treasure-hunting salvage into a rigorous scientific discipline that applies the same stratigraphic principles
ZF_5_01 — Autonomous Underwater Vehicles and Ocean Exploration Technology
Ocean exploration technology — from early human-occupied submersibles to modern autonomous underwater vehicles (AUVs) — has progressively opened the deep ocean to scientific investigation, driving transformative discover
ZF_4_13 — Ocean Noise Pollution: Anthropogenic Sound and Marine Life
Ocean noise pollution — the introduction of excessive or harmful human-generated sound into the marine environment — has emerged as one of the most pervasive and least visible threats to marine ecosystems. Sound travels
ZF_4_12 — Underwater Acoustics and the SOFAR Channel
Sound is the dominant long-range information carrier in the ocean — electromagnetic radiation (light, radio) is rapidly absorbed in seawater, but sound can travel thousands of kilometers with remarkably little loss, maki
ZF_4_04 — Ocean Acoustics and Sound Channels
Ocean acoustics — the study of sound propagation in the sea — is fundamental to marine science, military applications, and understanding marine life. Sound travels approximately 4.5× faster in seawater (~1,500 m/s) than
ZF_1_03 — Seafloor Spreading, Plate Tectonics and Marine Geology
The discovery that the ocean floor is not ancient and static but young, dynamic, and continuously recycled revolutionized Earth science in the 20th century. Seafloor spreading — proposed by Harry Hess (1962) and confirme
J_5_17 — Piezoelectric and Crystalline Technologies in Ancient and Modern Contexts
Piezoelectricity — the generation of electric charge from mechanical stress in certain crystalline materials, and conversely, the mechanical deformation of such materials under applied voltage — is one of the most import
G_1_11 — Underwater Remote Sensing — Multibeam, Magnetometry, Sub-Bottom Profiling
Underwater remote sensing encompasses a suite of geophysical survey technologies — multibeam echosounder (MBES), side-scan sonar (SSS), magnetometry, and sub-bottom profiler (SBP) — that enable archaeologists, oceanograp
D_4_05 — LiDAR Archaeology: Revolutionary Remote Sensing Discoveries
LiDAR (Light Detection and Ranging) has transformed archaeology by enabling researchers to see through dense vegetation and map landscapes at centimeter-level resolution, revealing previously unknown structures, roads, c
R_4_08 — Echolocation and the Evolution of Sensory Systems
The evolution of sensory systems represents some of the most striking convergent solutions to ecological challenges across the animal kingdom. Echolocation — the ability to emit sound pulses and interpret returning echoe
S_3_10 — Ocean Technology and Deep-Sea Exploration
The deep ocean remains Earth's most underexplored frontier — less than 25% of the ocean floor has been mapped at high resolution (>100 m), and only a tiny fraction has been directly observed or sampled. Human-occupied ve
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