Title: A Golden Age for Astrometry - Uncovering the Secrets of the Milky Way

Speaker: Martin Smith 研究员
Institute: 上海天文台
Time: 2017.11.02（Thursday） 14:30
Place: Physics Building 573, Haiyun Campus, Xiamen University

Abstract: For millennia we have measured the positions of stars in the heavens, leading to profound advances in our understanding of the universe. We are on the cusp of another such era, as new surveys are performing astrometry to unprecedented precision. These surveys have proved to be a fabulously rich resource for learning about our own Galaxy. I will discuss some important results from proper motion surveys, showing how the kinematics of stars around us can tell us much about both the disc and the halo of the Milky Way. Excitement in this field is now building due to the recent launch of the Gaia space astrometry satellite. This European-led mission is measuring the positions and velocities of stars to previously unimaginable precision, for the first time enabling ages to be measured for huge numbers of stars. I will show how stellar ages can be used to study the mass build-up of the Milky Way disc, which is a complex interplay between star formation and the diverse dynamical processes that dissipate stars throughout the disc. LAMOST has a crucial role to play, providing radial velocities and chemistry for millions of Gaia stars. With the first full data release due early next year, the Gaia-era is almost upon us. By driving progress in understanding our own Galaxy, such surveys will revolutionise our knowledge how galaxies form and evolve in the universe.