Mädler, Johann Heinrich Von

Born May 29, 1794, in Berlin; died Mar. 13 or 14, 1874, in Hanover. German astronomer.

From 1840 to 1865, Mädler worked in Russia; he was a professor at the University of Dorpat (Tartu) and director of the university’s observatory, where he continued V. Ia. Struve’s work on the observation of binary stars. Mädler also conducted new observations of the 3,222 stars in J. Bradley’s catalog and studied the proper motions of these stars. His “central sun” theory was the first attempt to study the structure of the Milky Way Galaxy on the basis of the motion of stars. However, his hypothesis that the center of the galaxy’s gravitation is located in the Pleiades star cluster proved to be unfounded. Mädler also compiled a detailed map of the moon and wrote a number of popular books on astronomy.