Does Iron occur in the Solar Corona?

Abstract

STRATTON¹ was able to recognize two 'forbidden' N II-lines in the beautiful photographs of the corona spectrum obtained by Sekiguti¹ at the total solar eclipse of June 19, 1936, and so to prove the occurrence of nitrogen in the solar corona. Moreover, Sekiguti noticed that two of the corona lines, λ 4815·9 and λ5738·0, on his photographs came very close to the nebular lines λ 4814·78 and λ 5737 in the spectrum of n-Carinæ. One of these two lines (λ 4814·78) is amongst those which Merrill² recognized as'forbidden' Fe II-lines. Should this identification be the correct one, this would mean that in addition to nitrogen another element, namely, iron, exists in the solar corona. In view of the interest generally taken in the chemical composition of the solar corona, we wish to discuss in some detail the possibility of such an identification.