Fundamental Properties of Nearby Northern and Southern Stars

Ianna，PhilipAST-9820711从观测到的邻近恒星的性质，可以大致推断出银河系中恒星的特征。这是我们可能希望知道的最完整的样本，甚至是最暗的恒星，也是拥有最好的观测数据的样本。事实上，许多距离最近的恒星缺乏基本的测量，如颜色、光谱类型，特别是距离，许多新的天体还有待发现。伊安娜博士的计划专注于提供这些基本数据，并通过三角视差方法确定距离，扩大附近恒星的样本，强调从南半球进行的CCD观测。他的计划包括一些已知的最暗的恒星，几颗棕矮星和亚矮星，这些恒星来自我们银河系中最古老的恒星群。他的调查还将发现双星，其质量将被确定。该观测方案将有助于完成太阳近邻的恒星普查，澄清光度和质量分布函数的暗端形式，有助于我们理解恒星群的形成和演化。

Ianna, PhilipAST-9820711The characteristics of stars populating our galaxy are broadly inferred from the observed properties of the nearby stars. This is the sample we might expect to be known most completely, down to the very faintest stars possible, and to have the best observational data. In fact, many of the nearest stars lack basic measurements such as colors, spectral types, and especially distances, and many new objects are yet to be discovered. Dr. Ianna's program focuses on providing these basic data and on expanding the sample of nearby stars through determination of distances by the trigonometric parallax method emphasizing CCD observations from the southern hemisphere. His program includes some of the faintest known stars, several brown dwarfs, and subdwarfs, stars from the oldest populations in our galaxy. His surveys will also discover binary stars, for which masses will be determined. The program of observations will help to complete the stellar census of the solar neighborhood, clarify the form of the faint end of the luminosity and mass distribution functions, and contribute to our understanding of the formation and evolution of stellar populations.