An Introduction to the Early Type Stars and to the Means of Observing Them

Abstract

The early type stars are relatively few in number and few of them are apparently bright, but because of their importance for studies of galactic structure and for studies of stellar structure, as well as because of the interesting problems presented by their spectra, numerous research papers have been devoted to them. Here an attempt is made to assemble much of the information that has been found so that the whole picture may be viewed critically. Two types of information exist: astrophysical information about the structure and constitution of early type stars, and kinematical information about the motions and distribution of these stars.