An extremely metal-deficient globular cluster in the Andromeda Galaxy
Publication Date
11-20-2020
Document Type
Article
Publication Title
Science
Volume
370
Issue
6519
DOI
10.1126/science.abb1970
First Page
970
Last Page
973
Abstract
Globular clusters (GCs) are dense, gravitationally bound systems of thousands to millions of stars. They are preferentially associated with the oldest components of galaxies, so measurements of their composition can constrain the build-up of chemical elements in galaxies during the early Universe.We report a massive GC in the Andromeda Galaxy (M31), RBC EXT8, that is extremely depleted in heavy elements. Its iron abundance is about 1/800 that of the Sun and about one-third that of the most iron-poor GCs previously known. It is also strongly depleted in magnesium. These measurements challenge the notion of a metallicity floor for GCs and theoretical expectations that massive GCs could not have formed at such low metallicities.
Funding Number
1748958
Funding Sponsor
National Science Foundation
Department
Physics and Astronomy
Recommended Citation
Søren S. Larsen, Aaron J. Romanowsky, Jean P. Brodie, and Asher Wasserman. "An extremely metal-deficient globular cluster in the Andromeda Galaxy" Science (2020): 970-973. https://doi.org/10.1126/science.abb1970
