Wolf was greatly impressed by the discovery of the sunspot cycle by Heinrich Schwabe and he not only carried out his own observations, but he collected all the available data on sunspot activity back as far as 1610 and calculated a period for the cycle of 11.1 years.
Heinrich Himmler | Heinrich Heine | Heinrich Schütz | Johann Heinrich Pestalozzi | Heinrich von Kleist | Heinrich Böll | Heinrich Isaac | Heinrich Marschner | Baron Hans Heinrich Thyssen-Bornemisza | Heinrich Mann | Heinrich Hertz | Heinrich Graetz | Heinrich Böll Foundation | Christian Heinrich Friedrich Peters | Wilhelm Heinrich Roscher | Johann Heinrich Lambert | Heinrich von Breymann | Heinrich Finck | Heinrich Zimmer | Heinrich Wilhelm Ernst | Heinrich Wilhelm Dove | Heinrich Wild | Heinrich von Bibra | Heinrich Schenker | Heinrich Nordhoff | Heinrich Leutemann | Heinrich Gustav Magnus | Ernst Heinrich Weber | Wilhelm Heinrich, Duke of Saxe-Eisenach | Wilhelm Heinrich |