Helge Stjernholm Kragh (born February 13, 1944) is a Danish historian of science who focuses on the development of 19th century physics, chemistry, and astronomy. His published work includes biographies of Paul Dirac, Julius Thomsen and Ludvig Lorenz, and The Oxford Handbook of the History of Modern Cosmology (2019) which he co-edited with Malcolm Longair.
Helge Kragh is a professor emeritus at the University of Aarhus, Denmark. He is known for his work on the history of physics, astronomy, and cosmology, as well as for his contributions to the history and philosophy of science. He studied physics and mathematics at the University of Copenhagen, where he received a PhD in the history of science in 1975. After completing his PhD, Kragh held various academic positions, including a postdoctoral research position at the Niels Bohr Institute and a professorship in the history of science at the University of Aarhus, where he worked from 1991 until his retirement in 2010.
Kragh has published numerous books and articles on the history of science, with a particular focus on the history of physics, astronomy, and cosmology. Some of his most notable works include "An Introduction to the Historiography of Science" (1987), "Cosmology and Controversy" (1996), and "Conceptions of Cosmos: From Myths to the Accelerating Universe" (2007).
In his research, Kragh has sought to understand the development of scientific ideas and theories in their historical context, and to examine the ways in which scientific knowledge has changed over time. He has also explored the relationship between science and other aspects of culture, such as religion and philosophy.
Kragh's work has been widely recognized and has had a significant impact on the field of the history of science. He has received numerous awards and honors for his contributions, including the Niels Bohr Medal for Outstanding Research in the History of Science and Ideas, the Bernal Prize for the Study of Science and Society, and the Pfister Prize for the History of Physics.
Kragh studied physics and chemistry at the University of Copenhagen, graduating with a degree in 1970. He earned his Ph.D. in physics in 1981 at the University of Roskilde. He received a second doctorate, in philosophy, from the University of Aarhus in 2007.
Kragh was an associate professor of history of science at Cornell University from 1987 to 1989, a professor at the University of Oslo from 1995 to 1997, and a professor at Aarhus University in Denmark from 1997 to 2015.
As of 2015 he retired, becoming emeritus professor at the Niels Bohr Institute at the University of Copenhagen. He is also a professor emeritus at the Centre for Science Studies of Aarhus University.
Kragh's areas of study are the history of physics from the mid-19th century onward, the history of astronomy, the history of cosmology and the history of chemistry. He is known for his work on the history of the periodic system, early quantum atomic models, speculative cosmology and the northern lights.