Life and achievements
Early life
Harry Hammond Hess was born on May 24, 1906, in New York City to a family with scholarly inclination. His father, Julian S. Hess, was a stockbroker, while his mother, Elizabeth Engel Hess, was interested in arts. Harry was born in Asbury Park, New Jersey, and attended high school there. Then, in 1923, he went to Yale University.
At the beginning of his studies, Hess wanted to become an electrical engineer but changed to geology, and this field became significant to him. He had to drop mineralogy in his first year but did not lose hope, so he graduated with a degree in geology. This was the starting point of his scientific career; he wanted to prove himself in a field in which he had once failed.
Hess then attended Yale University, and after he finished his studies, he worked as an exploration geologist in Northern Rhodesia, now Zambia, for two years. He gained a better perspective on the geological processes, and this made him develop an interest in the science of exploring the Earth. Hess finished his Ph.D. at Princeton University in 1932 under the guidance of Arthur Buddington, thus laying a solid academic background.
Soon after, he started working at Princeton University, where he spent most of his years. Despite the initial difficulties in his educational path, Hess's determination and commitment set the stage for his subsequent success in geology and other fields.
In his early career, Hess also joined the Navy-Princeton gravity expedition to the West Indies in 1932, where he helped take gravity measurements while on a submarine. This would later be useful in his wartime research on the ocean bottom. His academic positions and research in the 1930s enhanced his geological experience and knowledge, making him deeply concerned about the composition and behavior of the Earth's surface.
Legacy
Harry Hess's contribution to Earth's geology is immense, and his work on seafloor spreading is one of the most critical theories in modern plate tectonics. His theory gave the much-needed explanation to Alfred Wegener's earlier idea of continental drift and how the continents could shift on the Earth's surface.
Hess was able to revolutionize Earth's scientific community's understanding of the Earth's geologic processes through the idea that the oceanic crust forms at mid-ocean ridges and old oceanic crust is destroyed at oceanic trenches. His research answered questions concerning the age of oceanic sediments and the forces that control the movement of continents, therefore changing the face of earth sciences.
However, Hess's contribution to plate tectonics is not the only thing he left behind. He was instrumental in furthering the U. S. space program during the 1960s as he was the Chairman of the Space Science Board. This role proved that he is a versatile scientist with an interest in almost every field, from the bottom of the sea to space.
In appreciation of his contribution to geology and planetary science, the American Geophysical Union initiated the Harry H. Hess Medal in 1984 for exceptional research in the structure and development of the Earth and other planets. The award still goes to earth scientists who advance the frontiers of Earth science, and this is quite befitting of a man who revolutionized how we look at our planet.
Hess's work also influenced the generations of geologists and geophysicists who followed him, and his students and collaborators developed the ideas that Hess had initiated. Later studies of magnetic striping and seismic data supported his theory of seafloor spreading, which meant that his theories were well accepted in the scientific community during his lifetime. This acceptance enabled Hess to see the results of his work, a luxury for a scientist whose work revolutionized the field.
Even after he died in 1969, Hess's contributions are still felt within the scientific community. His concepts are still the basis of Earth's geology, and his approach to science is still considered the best for future generations.
Milestone moments
Mar 21, 1932
The Navy-Princeton Gravity Expedition to the West Indies
In 1932, Harry Hess went on a scientific expedition aboard the USS S-48, a U.S. Navy submarine, which was of great importance.
In this journey, Hess also helped Dr. Felix Vening Meinesz, a geophysicist from Utrecht University, conduct gravity measurements at sea using a new gravimeter Meinesz developed.
The voyage, which started at Guantanamo Bay in Cuba, passed through the Bahamas and returned to the same point, was an excellent opportunity for Hess to gain experience in oceanographic research.
This would later help him start studying the ocean floor and the theory of seafloor spreading.
It was one of the first examples of Hess's application of geology with naval engineering, a practice that would be more fully realized in wartime ocean floor mapping.
May 15, 1946
Discovery of Guyots
Hess was a navy captain during the Second World War, and in 1946, he made a discovery that would define his scientific career.
With the help of sonar equipment mounted on his ship, Hess explored the ocean floor and identified flat-topped submarine volcanoes, which he named 'Guyots' in honor of Arnold Henry Guyot.
This discovery revealed that volcanic activities were also possible underwater, sparking curiosity about the nature of the ocean bed.
Guyots helped Hess identify the dynamic nature of the seafloor, which led him to develop the seafloor spreading hypothesis.
The discovery of Guyots showed that the oceanic basins were not always as they are now and that the ocean floors had once been above sea level and then sunk.
Feb 12, 1959
First Steps in the Development of the Seafloor Spreading Hypothesis
In 1959, Harry Hess wrote a manuscript he shared with his colleagues and the scientific community as a working hypothesis on seafloor spreading.
His idea was that molten rock from the mantle comes up at the mid-ocean ridges and forms a new ocean floor, which then moves away from the ridge.
This hypothesis postulated that the ocean floor was an active structure that was being formed and destroyed at the ridges and trenches.
Although the scientific community did not accept Hess's theory because he had no direct evidence to support it, Hess's presentation sparked the scientific debate and paved the way for future confirmations.
Hess's idea extended Wegener's continental drift hypothesis but provided a way for the continents to move without cutting through the ocean floor.
Jan 25, 1962
Release of "History of Ocean Basins"
In 1962, Harry Hess published his first paper on the history of ocean basins, which explained the concept of seafloor spreading.
This paper described how material from the mantle rises through the crust at mid-ocean ridges, forms new oceanic crust, moves horizontally, and is then forced back into the mantle at trenches.
Hess's theory offered the scientific basis for explaining Alfred Wegener's earlier idea of continental drift, thus changing the perception of the Earth's dynamics.
The theory of seafloor spreading was not well received at first; however, it provided answers to difficult questions, such as the difference in age between oceanic sediments and continental rocks.
This publication is considered one of the most important for the progress of the plate tectonics theory and revolutionized the geology field.