Béla Harkányi, Baron

* Pest, April 11, 1869 – † Budapest, January 23, 1932 / astronomer, employee of the ; Ógyalla Observatory, corresponding member of the Hungarian Academy of Sciences (1911) ; ; He completed his secondary schooling in his hometown. From 1887, he studied mathematics, physics and astronomy at the universities of Pest, Leipzig, Strasbourg and Paris, then made a study trip to America. In 1896, he earned a doctorate in mathematics at the University of Pest. In 1899–1902, he took a position at the Ógyalla Observatory. In 1907, he was habilitated as a private teacher of astronomy at the University of Pest. He was a member of the House of the Order. He was the first in the world to theoretically determine the surface temperature of some stars (1901), and then the sizes of stars based on their temperatures (1910). His results were accompanied by great interest: the astronomers who dealt with the question [Bohlin (1860–1939), S. Arrhenius (1859–1927), then Lummer (1860–1925) and Pringsheim (1859–1917)] praised him. However, his work was interesting to physicists because it proved the validity of Planck's formula for high temperatures as well. He was an excellent mathematician. In the framework of his scientific study of Lake Balaton, he developed the theory of light reflection on rippling water surfaces and explained the formation of the so-called "golden bridge" created by the rising and setting sun. His literary work is significant, and he has published frequently in both Hungarian and German. ; ; His main works: ; A polka-löggság-völkerungs és tömm összögség és tömm összögség, 1896, ; Reflection phenomena of wavy water surfaces (also in German), 1905, ; Additions to the theory of the development of astronomy, 1922, ; On new stars, 1926.