报告摘要：Planetary nebulae (PNe) are descendants of the low- to intermediate-mass stars (1-8 solar masses), which account for the absolute majority (>90%) of the stellar populations in the universe. As the only interstellar media that exist in both galaxy disk and halo, PNe are widespread emission-line objects. They are one of the few classes of celestial objects that are active in almost every part of the electromagnetic spectrum, and have proven to be ideal laboratories to study various astrophysical processes and excellent tracers of the chemistry, dynamics and stellar population of host galaxies. In this talk, I will first briefly introduce the formation and evolution of PNe and related science, demonstrating their versatility as an astrophysical tool; then I focus on the chemical and morphological studies of PNe to probe the stellar and galaxy evolution, based on our previous observations using the ground and space telescopes.

主讲人简介：Dr. Xuan Fang is currently a research staff at National Astronomical Observatories, Chinese Academy of Sciences (NAOC). He obtained the Bachelor degree in physics at Wuhan University, and then PhD in astrophysics at Peking University. 2013.09-2016.02, he worked as a postdoc at Instituto de Astrofisica de Andalucia, Spanish National Research Council (IAA-CSIC). 2016.03-2019.12, he was a Postdoctoral Fellow at Laboratory for Space Research, the University of Hong Kong. Since 2020.01, he became a staff at NAOC, supported by a youth talent program of the Chinese Academy of Sciences. His research mainly focuses on the late-stage evolution of stars, in particular planetary nebulae and related sciences. He strives to carry out spectroscopy of PNe in the extended halo of Andromeda Galaxy (M31) using large ground-based telescopes, trying to understand the merging history of this largest spiral system in the Local Group.