Marcel G.J.
Minnaert

Utrecht (Physics Tree)


Gerard P.
Kuiper

University of Arizona


















Otto
Struve

UC Berkeley




Felix Christian
Klein

Universität Göttingen (Physics Tree)


Johannes Franz
Hartmann

Kuffner-Sternwarte


Richard
Schorr

University of Hamburg


Walter
Baade

Mount Wilson Observatory


Maarten
Schmidt

Caltech (Physics Tree)



Boudewijn F.
Roukema

Nicolaus Copernicus University
(Options)

Zbigniew
Buliński

Nicolaus Copernicus University

Jan Jakub
Ostrowski

Nicolaus Copernicus University

Boudewijn RoukemaX