Helge Kragh has been emeritus professor at the Niels Bohr Institute since 2015. He is former professor of history of science at Aarhus University, University of Oslo and Cornell University. Kragh holds doctorates in science and philosophy. His publication list includes more than 600 items, written for specialists as well as the general public. Most of his research is in the history of 19th century physics, chemistry, astronomy and cosmology.