Characteristic Temperatures in Super-Novae

Abstract

Some time ago Baade and I called attention to the existence of certain temporary and extremely luminous objects in extragalactic nebulae. [1] We suggested: 1. These temporary objects are individual stars which behave like giant analogues of common novae and which, therefore, may appropriately be called super-novae. 2. The visual brightness of super-novae, on the average, is comparable to the brightness of the nebulae themselves. 3. The average frequency of occurrence of super-novae is one per extragalactic nebula per several centuries. Recently the above suggestions have been verified to a great extent. A thorough investigation of past photographic records of temporary objects in nebulae by Baade, as well as the discovery in January, 1936, of a super-nova in N. G. C. 4273 have contributed much new evidence toward the verification of our super-nova hypothesis. It has also proved possible to establish between certain physical characteristics of temporary stars a number of relations which enable us to satisfactorily bridge the gap between common novae and super-novae. [2]