Groups of Degree n in Which the Largest Degree of a Substitution is a Minimum
G. A. Miller · Proceedings of the National Academy of Sciences · 1939
16 It should, however, be noted in this connection that Eddington (M.N., 96, 6 (1934)) has expressed the opinion that "in a normal region of interstellar space the hy- drogen will be entirely un-ionized, and indeed in molecular form."However, this conclusion rests upon "the photons of energy greater than 13.5 volts ...... having been absorbed and transmuted by the hydrogen near the stars."16 It would be interesting to improve this relation by a numerical computation similar to that which was carried out for He I by Struve and Wurm, Ap.