The Milky Way's disk in the age of Gaia

我建议研究银河系盘的特性，并由此推断出我们在宇宙中的家园是如何在宇宙时间内形成和演化的。经过一个世纪的详细研究，人们对银河系的许多最基本的特性仍然知之甚少。这包括它的质量，质量是如何从中心到外围分布的，其中有多少是暗物质，有多少恒星是在不同的时期形成的，具有什么化学性质，什么螺旋结构——当我们观察其他星系时就很清楚了——在银河系中是什么样的，它对恒星的运动有什么影响。现在正在进行新的恒星调查，测量大量恒星的距离、运动、年龄和化学丰度，这将极大地扩展研究银河系特性的可用数据。

I propose to investigate the properties of the Milky Way's disk and from this deduce how our home in the Universe formed and evolved over cosmic time. After a century of detailed study, many of the most basic properties of the Milky Way are still poorly understood. This includes its mass, how this mass is distributed from the center to the outskirts and how much of it is dark matter, how many stars are formed at different epochs and with what chemical properties, and what spiral structure---so clear when we look at other galaxies---looks like in the Milky Way and what effect it has on the motions of stars. New stellar surveys that measure the distances, motions, ages, and chemical abundances of large numbers of stars are being conducted now that will vastly expand the available data for investigating the properties of the Milky Way.