Preface.- 1 Introduction.- 2 Carl St rmer's Origins.- 3 St rmer's Auroral Studies.- 4 Mother-of-Pearl-, Noctilucent Clouds, Comets and Metors.- 5 Botanical Interests.- 6 Mathematical Analyses.- 7 Cooperation and conflict with Kristian Birkeland.- 8 St rmer the Man.- 9 The St rmer Family.- 10 St rmer's Accomplishments: In Retrospect.- 11 Carl St rmer's publications, biographies, and other sources. Appendix 1 St rmer's Trajectory Analyses.- Appendix...