Smithsonian Report. 1942. — Fleming 



PLATE 17 



Photographs OF the Aurora Borealis Which Accompanied the Geomagnetic Storm 



OF September 18, 1941. 

 (All times are mean 75° west meridian.) 

 (.4) 20'ilOn', Riverhead, Long Lsland, N'. Y.; looking west. (B) 20h]5m, Riverhead, Long Island, X. Y.; looking south 

 overhead; e.xposure ,30 seconds, f/2. (C) 20h20'", Riv'erhead, Long Island, X. Y.; looking northwest by north: note 

 Big T)i()per stars, including .\lcor: exposure 30 seconds, f/2. (I)) Riverliead, Long I.-^land, X. Y.: looking south over- 

 head; exposure 30 si>conds. r 2. (All ph()tograj)hs by Kurt W. Opperman.) 



