Harry Hammond Hess (May 24, 1906 – August 25, 1969) was an American

geologist A geologist is a scientist who studies the structure, composition, and History of Earth, history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the Field research, ...

and a

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

officer in

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

who is considered one of the "founding fathers" of the unifying theory of

plate tectonics Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed durin ...

. He published theories on

sea floor spreading Seafloor spreading, or seafloor spread, is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. History of study Earlier theories by Alfred Wegener ...

, specifically on relationships between

island arc Island arcs are long archipelago, chains of active volcanoes with intense earthquake, seismic activity found along convergent boundary, convergent plate tectonics, tectonic plate boundaries. Most island arcs originate on oceanic crust and have re ...

s, seafloor gravity anomalies, and serpentinized

peridotite Peridotite ( ) is a dense, coarse-grained igneous rock consisting mostly of the silicate minerals olivine and pyroxene. Peridotite is ultramafic, as the rock contains less than 45% silica. It is high in magnesium (Mg2+), reflecting the high pr ...

, suggesting that the convection in the Earth's mantle is the driving force behind this process.

Early life and education

Harry Hammond Hess was born on May 24, 1906, in

New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...

to Julian S. Hess, a member of the

New York Stock Exchange The New York Stock Exchange (NYSE, nicknamed "The Big Board") is an American stock exchange in the Financial District, Manhattan, Financial District of Lower Manhattan in New York City. It is the List of stock exchanges, largest stock excha ...

, and Elizabeth Engel Hess. He attended

Asbury Park High School Asbury Park High School is a comprehensive, community public high school serving students in seventh through twelfth grades. It is in a landmark building in Asbury Park, in Monmouth County, in the U.S. state of New Jersey, that was constru ...

Asbury Park, New Jersey Asbury Park () is a beachfront city located on the Jersey Shore in Monmouth County in the U.S. state of New Jersey. It is part of the New York metropolitan area. As of the 2020 United States census, the city's population was 15,188, a decr ...

. In 1923, he entered

Yale University Yale University is a Private university, private Ivy League research university in New Haven, Connecticut, United States. Founded in 1701, Yale is the List of Colonial Colleges, third-oldest institution of higher education in the United Stat ...

, where he intended to study

electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...

but ended up graduating with a

Bachelor of Science A Bachelor of Science (BS, BSc, B.S., B.Sc., SB, or ScB; from the Latin ') is a bachelor's degree that is awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Scienc ...

degree in geology. Hess failed his first time taking mineralogy at Yale and was told he had no future in the field. Despite this, he continued with his degree and was teaching geology at Princeton when World War II was declared. He spent two years as an exploration geologist in

Northern Rhodesia Northern Rhodesia was a British protectorate in Southern Africa, now the independent country of Zambia. It was formed in 1911 by Amalgamation (politics), amalgamating the two earlier protectorates of Barotziland-North-Western Rhodesia and North ...

. In 1934 he married Annette Burns.

Teaching career

Harry Hess taught for one year (1932–1933) at

Rutgers University Rutgers University ( ), officially Rutgers, The State University of New Jersey, is a Public university, public land-grant research university consisting of three campuses in New Jersey. Chartered in 1766, Rutgers was originally called Queen's C ...

New Jersey New Jersey is a U.S. state, state located in both the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. Located at the geographic hub of the urban area, heavily urbanized Northeas ...

and spent a year as a research associate at the

Geophysical Laboratory The Carnegie Institution for Science, also known as Carnegie Science and the Carnegie Institution of Washington, is an organization established to fund and perform scientific research in the United States. This institution is headquartered in Wa ...

Washington, D. C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

, before joining the faculty of

Princeton University Princeton University is a private university, private Ivy League research university in Princeton, New Jersey, United States. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial ...

in 1934. Hess remained at Princeton for the rest of his career and served as Geology Department Chairman from 1950 to 1966. He was a visiting professor at the

University of Cape Town The University of Cape Town (UCT) (, ) is a public university, public research university in Cape Town, South Africa. Established in 1829 as the South African College, it was granted full university status in 1918, making it the oldest univer ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

(1949–1950), and the

University of Cambridge The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

(1965).

The Navy-Princeton gravity expedition to the West Indies in 1932

Hess accompanied Dr. Felix Vening Meinesz of

Utrecht University Utrecht University (UU; , formerly ''Rijksuniversiteit Utrecht'') is a public university, public research university in Utrecht, Netherlands. Established , it is one of the oldest universities in the Netherlands. In 2023, it had an enrollment of ...

on board the US Navy submarine USS S-48 to assist with the second U.S. expedition to obtain gravity measurements at sea. The expedition used a

gravimeter Gravimetry is the measurement of the strength of a gravitational field. Gravimetry may be used when either the magnitude of a gravitational field or the properties of matter responsible for its creation are of interest. The study of gravity c ...

, or gravity meter, designed by Meinesz. The submarine traveled a route from Guantanamo, Cuba, to

Key West, Florida Key West is an island in the Straits of Florida, at the southern end of the U.S. state of Florida. Together with all or parts of the separate islands of Sigsbee Park, Dredgers Key, Fleming Key, Sunset Key, and the northern part of Stock Islan ...

, and return to Guantanamo through the

Bahamas The Bahamas, officially the Commonwealth of The Bahamas, is an archipelagic and island country within the Lucayan Archipelago of the Atlantic Ocean. It contains 97 per cent of the archipelago's land area and 88 per cent of its population. ...

and

Turks and Caicos The Turks and Caicos Islands (abbreviated TCI; and ) are a British Overseas Territory consisting of the larger Caicos Islands and smaller Turks Islands, two groups of tropical islands in the Lucayan Archipelago of the Atlantic Ocean and no ...

region from 5 February through 25 March 1932. The description of operations and results of the expedition were published by the U.S. Navy Hydrographic Office in ''The Navy-Princeton gravity expedition to the West Indies in 1932''.

Military and war career

Hess joined the

during World War II, becoming

captain Captain is a title, an appellative for the commanding officer of a military unit; the supreme leader or highest rank officer of a navy ship, merchant ship, aeroplane, spacecraft, or other vessel; or the commander of a port, fire or police depa ...

of the USS ''Cape Johnson'', an attack transport ship equipped with a new technology:

sonar Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects o ...

. This command would later prove to be key in Hess's development of his theory of

. Hess carefully tracked his travel routes to

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

landings on the

Marianas The Mariana Islands ( ; ), also simply the Marianas, are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly Volcano#Dormant and reactivated, dormant volcanic mountains in the northwestern Pacific Ocean ...

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

, and

Iwo Jima is one of the Japanese Volcano Islands, which lie south of the Bonin Islands and together with them make up the Ogasawara Subprefecture, Ogasawara Archipelago. Together with the Izu Islands, they make up Japan's Nanpō Islands. Although sout ...

, continuously using his ship's

echo sounder Echo sounding or depth sounding is the use of sonar for ranging, normally to determine the depth of water (bathymetry). It involves transmitting acoustic waves into water and recording the time interval between emission and return of a pulse; ...

. This unplanned wartime scientific surveying enabled Hess to collect ocean floor profiles across the North

, resulting in the discovery of flat-topped submarine volcanoes, which he termed

guyot In marine geology, a guyot (), also called a tablemount, is an isolated underwater volcanic mountain (seamount) with a flat top more than below the surface of the sea. The diameters of these flat summits can exceed . Guyots are most commonly fo ...

s, after the 19th-century geographer

Arnold Henry Guyot Arnold Henry Guyot ( ) (September 28, 1807February 8, 1884) was a Swiss-American geologist and geographer. Early life Guyot was born on September 28, 1807, at Boudevilliers, near Neuchâtel, Switzerland. He was educated at Chaux-de-Fonds, then ...

. After the war, he remained in the Naval Reserve, rising to the rank of

rear admiral Rear admiral is a flag officer rank used by English-speaking navies. In most European navies, the equivalent rank is called counter admiral. Rear admiral is usually immediately senior to commodore and immediately below vice admiral. It is ...

Scientific discoveries

In 1960, Hess made his single most important contribution, which is regarded as part of the major advance in geologic science of the 20th century. In a widely circulated report to the

Office of Naval Research The Office of Naval Research (ONR) is an organization within the United States Department of the Navy responsible for the science and technology programs of the U.S. Navy and Marine Corps. Established by Congress in 1946, its mission is to plan ...

, he advanced the theory, now generally accepted, that the Earth's crust moved laterally away from long, volcanically active

oceanic ridges A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of about and rises about above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a div ...

. He only understood his ocean floor profiles across the North Pacific Ocean after

Marie Tharp Marie Tharp (July 30, 1920 – August 23, 2006) was an American geologist and oceanographic cartographer. In the 1950s, she collaborated with geologist Bruce Heezen to produce the first scientific map of the Atlantic Ocean floor. Her cartogr ...

and Bruce Heezen (1953, Lamont Group) discovered the

Great Global Rift A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of about and rises about above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a div ...

, running along the

Mid-Atlantic Ridge The Mid-Atlantic Ridge is a mid-ocean ridge (a Divergent boundary, divergent or constructive Plate tectonics, plate boundary) located along the floor of the Atlantic Ocean, and part of the List of longest mountain chains on Earth, longest mountai ...

. ''

Seafloor spreading Seafloor spreading, or seafloor spread, is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. History of study Earlier theories by Alfred Wegener ...

'', as the process was later named, helped establish

Alfred Wegener Alfred Lothar Wegener (; ; 1 November 1880 – November 1930) was a German climatologist, geologist, geophysicist, meteorologist, and polar researcher. During his lifetime he was primarily known for his achievements in meteorology and ...

's earlier (but generally dismissed at the time) concept of

continental drift Continental drift is a highly supported scientific theory, originating in the early 20th century, that Earth's continents move or drift relative to each other over geologic time. The theory of continental drift has since been validated and inc ...

as scientifically respectable. This triggered a revolution in the earth sciences. Hess's report was formally published in his
History of Ocean Basins
' (1962), which for a time was the single most referenced work in solid-earth

geophysics Geophysics () is a subject of natural science concerned with the physical processes and Physical property, properties of Earth and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists conduct i ...

. Hess was also involved in many other scientific endeavours, including the

Mohole Project Mohole was an attempt in the early 1960s to drill through the Earth's Crust (geology), crust to obtain samples of the Mohorovičić discontinuity, or Moho, the boundary between the Earth's Crust (geology), crust and Mantle (geology), m ...

project (1957–1966), an investigation onto the feasibility and techniques of deep sea drilling.

Accolades and affiliations

Hess was elected to the United States

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...

in 1952 and the

American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

in 1960. He was president of

The Geological Society of America The Geological Society of America (GSA) is a nonprofit organization dedicated to the advancement of the geosciences. History The society was founded in Ithaca, New York, in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitch ...

in 1963 and received their

Penrose Medal The Penrose Medal was created in 1925 by R.A.F. Penrose, Jr., as the top prize awarded by the Geological Society of America. Originally created as the Geological Society of America Medal it was soon renamed the Penrose Medal by popular assent of ...

in 1966. In 1968, he was elected to the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...

Death

Hess died from a

heart attack A myocardial infarction (MI), commonly known as a heart attack, occurs when Ischemia, blood flow decreases or stops in one of the coronary arteries of the heart, causing infarction (tissue death) to the heart muscle. The most common symptom ...

Woods Hole, Massachusetts Woods Hole is a census-designated place in the town of Falmouth in Barnstable County, Massachusetts, United States. It lies at the extreme southwestern corner of Cape Cod, near Martha's Vineyard and the Elizabeth Islands. The population was 78 ...

, on August 25, 1969, while chairing a meeting of the Space Science Board of the

. He was buried at

Arlington National Cemetery Arlington National Cemetery is the largest cemetery in the United States National Cemetery System, one of two maintained by the United States Army. More than 400,000 people are buried in its 639 acres (259 ha) in Arlington County, Virginia. ...

and was posthumously awarded the National Aeronautics and Space Administration's Distinguished Public Service Award.

The Harry H. Hess Medal

The

American Geophysical Union The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, Atmospheric science, atmospheric, Oceanography, ocean, Hydrology, hydrologic, Astronomy, space, and Planetary science, planetary scientists and enthusiasts that ...

established the Harry H. Hess medal in his memory in 1984 to "honor outstanding achievements in research of the constitution and evolution of Earth and sister planets."

Past recipients

Source: * 1985 Gerald J. Wasserburg * 1987 Julian R. Goldsmith * 1989 A.G.W. Cameron * 1991 George W. Wetherill * 1993 Alfred E. Ringwood * 1995 Edward Anders * 1996 Thomas J. Ahrens * 1997 Stanley Robert Hart * 1998

David J. Stevenson David John Stevenson (born 2 September 1948) is a professor of planetary science at Caltech. Originally from New Zealand, he received his Ph.D. from Cornell University in physics, where he proposed a model for the interior of Jupiter. He is well ...

* 1999 Ikuo Kushiro * 2001 Albrecht Hofmann * 2002

Gerald Schubert Gerald Schubert (born 1939) is a geophysicist and Professor Emeritus of Earth, Planetary, and Space Sciences at UCLA. His research has broadly dealt with modeling the structure and dynamics of the interiors and atmospheres and Earth and other planet ...

* 2003 David L. Kohlstedt * 2004

Adolphe Nicolas Adolphe Nicolas (18 February 1936 – 31 March 2020) was a French geologist, specializing in tectonics and petrophysics. Biography Born in 1936 in Rennes, Nicolas lived in Morocco following World War II, where his father worked as a doctor for t ...

* 2005 Sean C. Solomon * 2006

Alexandra Navrotsky Alexandra Navrotsky (born 20 June 1943 in New York City) is a physical chemist in the field of nanogeoscience. She is an elected member of the United States National Academy of Sciences (NAS) and the American Philosophical Society (APS). She w ...

* 2007 Michael John O'Hara * 2008 H. Jay Melosh * 2009 Frank M. Richter * 2010 David Walker * 2011 Henry Dick * 2012 Maria T. Zuber * 2013 Bernard Wood * 2014 Donald J. DePaolo * 2015

Claude Jaupart Claude Jaupart (born 22 May 1953) is a French geophysicist and a member of the French Academy of Sciences (since December 2008). Biography Professor of geophysics at the University of Paris-Diderot, and a researcher in physical volcanology, he i ...

* 2016

Alexander Halliday Sir Alexander Norman Halliday (born 11 August 1952) is a British geochemist and academic who is the Founding Dean Emeritus of the Columbia Climate School, and Director of the Earth Institute at Columbia University. He joined the Earth Institu ...

* 2017

Roberta Rudnick Roberta L. Rudnick (born 1958) is an American earth scientist and professor of geology at the University of California, Santa Barbara. She was elected a member of the National Academy of Sciences in 2010 and was awarded the Dana Medal by the Mine ...

* 2018 Timothy L. Grove * 2019 Richard J. Walker * 2020 Donald B. Dingwell * 2021 Peter B. Kelemen * 2022

Janne Blichert-Toft Janne Blichert-Toft is a geochemist, specializing in the use of isotopes with applications in understanding planetary mantle- crust evolution, as well as the chemical composition of matter in the universe. To further this research, Blichert-To ...

* 2023 Catherine A. McCammon

Selected publications

* **Also in: *** *** * * * * * **Also in: *** * *

References

External links

Harry Hess (1906–1969) A Science Odyssey: People and Discoveries
taken from
AGU Harry H. Hess Medal
{{DEFAULTSORT:Hess, Harry American geophysicists Asbury Park High School alumni Tectonicists Scientists from New York City United States Navy rear admirals (upper half) 1906 births 1969 deaths Academic staff of the University of Cape Town Yale University alumni Burials at Arlington National Cemetery Penrose Medal winners Princeton University faculty Rutgers University faculty Presidents of the Geological Society of America Marine geophysicists Members of the American Philosophical Society