The growing trove of precision astrometric observations from the Gaia space telescope and other surveys is revealing the structure and dynamics of the Milky Way in ever more exquisite detail. We summarize the current status of our understanding of the structure and the characteristics of the Milky Way, and we review the emerging picture: the Milky Way is evolving through interactions with the massive satellite galaxies that stud its volume, with evidence pointing to a cataclysmic past. It is also woven with stellar streams, and observations of streams, satellites, and field stars offer new constraints on its dark matter, both on its spatial distribution and its fundamental nature. The recent years have brought much focus to the study of dwarf galaxies found within our Galaxy’s halo and their internal matter distributions. In this review, we focus on the predictions of the cold dark matter paradigm at small mass scales through precision astrometric measurements, and we summarize the modern consensus on the extent to which small-scale probes are consistent with this paradigm. We note the discovery prospects of these studies, and also how they intertwine with probes of the dynamics and evolution of the Milky Way in various and distinct ways.

来自盖亚的精密天体测量观测的宝库越来越多太空望远镜和其他巡天正在以更加精致的细节揭示银河系的结构和动力学。我们总结了我们对银河系结构和特征的理解的现状，并回顾了新出现的图片：银河系正在通过与研究其体积的巨大卫星星系的相互作用而演化，有证据表明它经历了灾难性的过去. 它也与恒星流交织在一起，对流、卫星和场星的观测为其暗物质提供了新的限制，包括空间分布和基本性质。近年来，人们对在我们银河系晕内发现的矮星系及其内部物质分布的研究引起了很多关注。在这次审查中，我们专注于通过精确的天体测量在小质量尺度上预测冷暗物质范式，我们总结了现代关于小尺度探测器与这种范式一致的程度的共识。我们注意到这些研究的发现前景，以及它们如何以各种不同的方式与对银河系动力学和演化的探索交织在一起。