Eclipses 



equatorial zone of the orb, that is to say, in 

 the region of its surface most remote from the 

 axis around which it turns. These are the 

 protuberances which had been revealed to the 

 learned world by the observation of eclipses 

 before the spectroscopic method of Janssen and 

 Lockyer enabled them to be studied in a 

 continuous and systematic manner. Beyond 

 stretches the corona. It is difficult to estimate 

 the total luminosity of this corona, owing to the 

 great variations of light which accompany the 

 very short phenomenon of the eclipse; it has, 

 however, been compared to that of the full 

 moon. 



We are able to distinguish in the corona two 

 different regions the internal corona of a 

 silvery white colour, on which stand out the 

 reddish projections of the protuberances; then, 

 all around, a less bright region, often called the 

 halo ) because its appearance recalls the luminous 

 circle that painters draw round the heads of 

 their saints. The halo seems to consist of long 

 plumes, some straight and some bent. It is, 

 however, worthy of note that whereas the 

 protuberances and the photosphere itself are in 



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