BAADE; Walter W.H.; 1893-1960; GER/USA

His works made it possible to distinguish two different stellar populations (I and II) in the Milky Way, but also to rectify the HUBBLE distance measurements because BAADE showed that cepheids were not all sharing the same caracteristics. He published studies on polarisation and synchroton effect and made the link between the Crab Nebula and 1054's supernova.