Smithsonian Report. 1951. W. O. Roberts 



Plate 1 



1. Large eruptive prominence of June 4, 1946, photographed in hydrogen light, 6563 A. 

 The prominence is shown rising in an enormous arch above the edge of the artificially 

 eclipsed sun. The immense cloud of h\drogen rose to a height of hundreds of thousands 

 of miles in less than 2 hours. 



SPECTRUM OF WEST LIMB 



12 FEBRUARY 1947 



6563 A 

 PROM. 



COR. 



PROM. 



FeXIV 



5303 A 



COR. 



Sections from a spectrogram of the limb of the sun showing emission lines ol the 

 corona and of prominences. The emission spectra at the bottom of the plate came 

 from an intensely disturbed region of the sun's surface. The region displays abnormally 

 bright emission from the red coronal line (6374 A) as well as spectra from a high-velocity 

 prominence associated with a sunspot group. 



