Reconstructing the Formation of the Milky Way with Metal-Poor Stars

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

The investigator seeks to understand the early formation history of our Milky Way galaxy. She will do so by observing the oldest known stars with large optical telescopes. Due to detectable signatures of elements in the optical spectra of these stars, the stars show the birth environments, some 12 billion years ago. The investigator will study the chemical composition of these old stars. By detailed modeling, astronomers to reconstruct how the first stars and the first galaxies formed. Such information provides insight into how our Galaxy formed from many small galaxies long ago. Her research has shown that certain elements were formed in specific types of massive supernova explosions and other explosive events. Mapping the locations of old stars in the Galaxy also assists with the modeling of the change in time of the composition of the Milky Way. To share her research experience with the public, the investigator has developed a theatrical production highlighting fundamental contributions by nuclear physicist Lise Meitner. Ms. Meitner overcame many challenges to make her research discoveries, despite stress and persecution during World Wars I and II. The investigator will use high-resolution spectroscopy. She will measure detailed the element signatures of different types of old stars. It provides knowledge on their cosmic histories. This will allow her to characterize the sites in the cosmos where the heaviest elements are made. She will also map the explosive deaths of the first stars. The properties of small satellite dwarf galaxies will be established. This will provide insight into the formation history of the Milky Way. Results will be compared to theoretical models and simulations. The results of this study will constrain nucleosynthesis models, and partially explain the relative abundances of elements found on Earth. The investigator’s study of the relationship between past element creation and current, explosive, multi-messenger observations, place the new observations in a historical context. This award is partially funded through the NSF Windows on the Universe (WoU) Big Idea allocation. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.