报告摘要：The oldest stars of our Galaxy, the Milky Way, are messagers from the very early times. I will show how we can use the combined power of detailed astrometric, photometric, and spectroscopic observations of our surroundings to constrain the formation of the first stellar structures and the first galaxies.

主讲人简介：Dr. Nicolas Martin is a tenured CNRS researcher at the Strasbourg astronomical Observatory. He obtained his PhD from the Strasbourg University in France in 2006. He then worked as a postdoctoral fellow at the Max Plank Institute for Astronomy in Heidelberg before joining the CNRS in 2012. He specializes in observations of dwarf galaxies and stellar streams in the Milky Way and Andromeda to understand galaxy formation. Dr. Martin was a member of the CFHT Science Council from 2016 to 2021 and was the Chair of the CFHT French Time Allocation Committee. He was the head of the Pan-STARRS1 Local Group Key Project and is now the leader of the Pristine survey that combines more than 300 nights of telescope time. He has published more than 260 papers with ~18,000 citations (h-index 66) including 4 Nature papers (1 as first author).