Development, Operation and Maintenance of the Automated Plate Scanner

在我们对两者的理解中， 星系和恒星的演化是关于 恒星的成分和演化可能取决于化学物质 组成，初始质量函数的可能变化， 星星的形成，特别是对形态类型的 银河 这里概述的研究计划将提供一些 开始回答这些问题所需的观测数据 问题. 具体来说，一个恒星的内容调查附近的Sb型 螺旋星系M31将进行。 A的初步结果 对M31中最亮的恒星的调查表明，它们比M31中的其他恒星要小。 比Sc螺旋星系和麦哲伦星系中的对应物更明亮 不规则星系 第一次观察表明， 最大质量恒星的演化可能取决于 形态类型 对星星形成区的研究 在奇特的半人马座A星系中将完成。 对非常明亮的超巨星的研究， Hertzsprung-Russell（HR）图中的上光度边界 包括哈勃-桑德奇变量和冷却器 超巨星，将被执行。 定量光谱 奇异A型超巨星的研究 强氢线已经开始。 这些恒星可能是 在氦燃烧阶段演化出超巨星。他们的 在HR图上的标识和位置非常重要 用于恒星演化研究

Among the basic uncertainties in our understanding of both galactic and stellar evolution are questions concerning how the stellar content and evolution of the stars may depend on chemical composition, possible variations in the initial mass function of star formation, and especially on the morphological type of the galaxy. The research program outlined here will provide some of the observational data necessary to begin answering these questions. Specifically, a stellar content survey of the nearby Sb-type spiral galaxy M31 will be carried out. The initial results of a survey of the brightest stars in M31 show that they are less luminous than their counterparts in Sc spirals and the Magellanic irregular galaxies. This first look suggests that the formation and evolution of the most massive stars may depend on the morphological type. An investigation of the star forming regions in the peculiar galaxy Centaurus A will be done. Studies of the very luminous hypergiant stars, which define the upper luminosity boundary in the Hertzsprung-Russell (HR) diagram and includes the Hubble-Sandage variables and the cooler hypergiants, will be carried out. A quantitative spectroscopic study of the peculiar A-type supergiant stars with anomalously strong hydrogen lines has begun. These stars may be the more evolved supergiant stars in the Helium burning stage. Their identification and location on the HR diagram is very important for stellar evolution studies.