The Age of the Stars

Abstract

It is well-known that the supply of energy made available by the gravitational contraction of the material of a star is insufficient, in view of the Stefan law of total radiation, to allow the time-life of a star to be more than a small fraction of the age demanded by geological considerations. Discussions of the problem of maintenance of stellar energy have been given by Shapley¹ and Russell.² The former discusses an hypothesis of asymmetrical radiation flow in which the rate of radiation to empty space is much less than the radiation toward other matter. Shapley also considers the destruction of mass as a possible source of stellar energy. He concludes that “ … it now appears that the disagreement between the long and short time scales must be decided the favor of an exceedingly prolonged history for sidereal systems, permitting a relatively slow evolutionary development for stars and planets.” Russell’s paper is a very general sketch of the main outlines of the problem and is concerned mainly with the conditions under which a nuclear “unknown” source of energy comes into action.

Read before the Academy November 11,1924