The Challenger Deep is the deepest known point of the seabed of Earth, located in the western Pacific Ocean at the southern end of the Mariana Trench, in the ocean territory of the Federated States of Micronesia. According to the GEBCO Gazetteer of Undersea Feature Names the depression's depth is 10,920 ± 10 m (35,827 ± 33 ft) at 11°22.4′N142°35.5′E, although its exact geodetic location remains inconclusive and its depth has been measured at 10,902–10,929 m (35,768–35,856 ft) by deep-diving submersibles, remotely operated underwater vehicles, benthic landers, and sonar bathymetry. The differences in depth estimates and their geodetic positions are scientifically explainable by the difficulty of researching such deep locations.
The Mariana Trench is an oceanic trench located in the western Pacific Ocean, about 200 kilometres (124 mi) east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width. The maximum known depth is 10,984 ± 25 metres at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. The deepest point of the trench is more than 2 km (1.2 mi) farther from sea level than the peak of Mount Everest.
Oceanography, also known as oceanology, sea science and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics; plate tectonics and seabed geology; and fluxes of various chemical substances and physical properties within the ocean and across its boundaries. These diverse topics reflect multiple disciplines that oceanographers utilize to glean further knowledge of the world ocean, including astronomy, biology, chemistry, geography, geology, hydrology, meteorology and physics. Paleoceanography studies the history of the oceans in the geologic past. An oceanographer is a person who studies many matters concerned with oceans, including marine geology, physics, chemistry, and biology.
Geophysics is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists, who usually study geophysics, physics, or one of the Earth sciences at the graduate level, complete investigations across a wide range of scientific disciplines. The term geophysics classically refers to solid earth applications: Earth's shape; its gravitational, magnetic fields, and electromagnetic fields ; its internal structure and composition; its dynamics and their surface expression in plate tectonics, the generation of magmas, volcanism and rock formation. However, modern geophysics organizations and pure scientists use a broader definition that includes the water cycle including snow and ice; fluid dynamics of the oceans and the atmosphere; electricity and magnetism in the ionosphere and magnetosphere and solar-terrestrial physics; and analogous problems associated with the Moon and other planets.
The Challenger expedition of 1872–1876 was a scientific programme that made many discoveries to lay the foundation of oceanography. The expedition was named after the naval vessel that undertook the trip, HMS Challenger.
The Woods Hole Oceanographic Institution is a private, nonprofit research and higher education facility dedicated to the study of marine science and engineering.
William Maurice "Doc" Ewing was an American geophysicist and oceanographer.
J. Lamar Worzel was an American geophysicist known for his important contributions to underwater acoustics, underwater photography, and gravity measurements at sea.
HMS Challenger was a survey ship of the United Kingdom's Royal Navy associated with the discovery of Challenger Deep, the deepest point in the oceans. She was laid down in 1930 at Chatham Dockyard and built in a dry dock, before being moved to Portsmouth for completion and commissioning on 15 March 1932.
A research vessel is a ship or boat designed, modified, or equipped to carry out research at sea. Research vessels carry out a number of roles. Some of these roles can be combined into a single vessel but others require a dedicated vessel. Due to the demanding nature of the work, research vessels may be constructed around an icebreaker hull, allowing them to operate in polar waters.
Marine geology or geological oceanography is the study of the history and structure of the ocean floor. It involves geophysical, geochemical, sedimentological and paleontological investigations of the ocean floor and coastal zone. Marine geology has strong ties to geophysics and to physical oceanography.
The Lamont–Doherty Earth Observatory (LDEO) is the scientific research center of the Columbia Climate School, and a unit of The Earth Institute at Columbia University. It focuses on climate and earth sciences and is located on a 189-acre campus in Palisades, New York, 18 miles (29 km) north of Manhattan on the Hudson River.
Walter Heinrich Munk was an American physical oceanographer. He was one of the first scientists to bring statistical methods to the analysis of oceanographic data. Munk worked on a wide range of topics, including surface waves, geophysical implications of variations in the Earth's rotation, tides, internal waves, deep-ocean drilling into the sea floor, acoustical measurements of ocean properties, sea level rise, and climate change. His work won awards including the National Medal of Science, the Kyoto Prize, and induction to the French Legion of Honour.
Biological oceanography is the study of how organisms affect and are affected by the physics, chemistry, and geology of the oceanographic system. Biological oceanography may also be referred to as ocean ecology, in which the root word of ecology is Oikos (oικoσ), meaning ‘house’ or ‘habitat’ in Greek. With that in mind, it is of no surprise then that the main focus of biological oceanography is on the microorganisms within the ocean; looking at how they are affected by their environment and how that affects larger marine creatures and their ecosystem. Biological oceanography is similar to marine biology, but is different because of the perspective used to study the ocean. Biological oceanography takes a bottom-up approach, while marine biology studies the ocean from a top-down perspective. Biological oceanography mainly focuses on the ecosystem of the ocean with an emphasis on plankton: their diversity ; their productivity and how that plays a role in the global carbon cycle; and their distribution.
Deep-sea exploration is the investigation of physical, chemical, and biological conditions on the ocean waters and sea bed beyond the continental shelf, for scientific or commercial purposes. Deep-sea exploration is an aspect of underwater exploration and is considered a relatively recent human activity compared to the other areas of geophysical research, as the deeper depths of the sea have been investigated only during comparatively recent years. The ocean depths still remain a largely unexplored part of the Earth, and form a relatively undiscovered domain.
The historical development of geophysics has been motivated by two factors. One of these is the research curiosity of humankind related to planet Earth and its several components, its events and its problems. The second is economical usage of Earth's resources and Earth-related hazards such as earthquakes, volcanoes, tsunamis, tides, and floods.
Marine biology is a hybrid subject that combines aspects of organismal function, ecological interaction and the study of marine biodiversity. The earliest studies of marine biology trace back to the Phoenicians and the Greeks who are known as the initial explorers of the oceans and their composition. The first recorded observations on the distribution and habits of marine life were made by Aristotle.
George G. Shor Jr. was an American marine geophysicist. His entire career was at the Scripps Institution of Oceanography in La Jolla, California. He began his career working with the Mohole Project, an ambitious project that attempted to drill to the Mohorovičić discontinuity from deep-ocean regions.
HMS Lightning, launched in 1823, was a paddle steamer, one of the first steam-powered ships on the Navy List. She served initially as a packet ship, but was later converted into an oceanographic survey vessel.
