Adriaan van Maanen



On rotations in spiral nebulae:


Measurements of motions in the spiral nebula M101 [superimposed on negative image of this nebula; from the Astrophysical Journal, 44 (1916), 210-28]
First page of van Maanen's 1916 article on rotations in spiral nebulae [from the Astrophysical Journal, 44 (1916): 210-11. [Large file -- may take time to load.]