NSF Award
2406594
About 85% of the mass in the Universe is thought to be dark matter. Dark matter is theoretically made up of particles that have mass, but can pass right through ordinary matter, like the Earth. These particles are thought to exist because they are needed to explain the motions of stars and galaxies. These visible objects are moving as if being tugged by gravitational forces of some unseen masses. However, dark matter has never been directly detected. The investigator will observe small galaxies that are close to our own Milky Way galaxy to learn how accurately the dark matter in these small galaxies can be measured. This project supports a graduate student who will lead activities for the Flying Cloud Institute for Young Women in Science (YWIS). YWIS offers after-school science club laboratories and a summer camp for middle school girls who are interested in science. The investigator leads the MilkyWay@home project. In this project thousands of people volunteer their computers to help MilkyWay@home do research, and these citizens also follow the research developments. In addition, this project funds summer research experiences for three undergraduate students. <br/><br/>This project aims to quantify the systematic errors in measurements of the dark matter mass of dwarf galaxy satellites of the Milky Way from observations of tidal streams. When a smaller galaxy falls into the Milky Way, our galaxy’s gravitational tidal forces pull it apart and its stars are spread along its orbit into a long “stream” of stars. The key goal is to understand the amount of dark matter in the Large Magellanic Cloud (LMC), the largest of the small galaxies that orbit around the Milky Way galaxy. Another goal is to figure out how well we can determine the amount of dark matter in a small galaxy that used to orbit around the Milky Way, but now has been ripped apart by our Galaxy’s gravity. Now, the stars from this small galaxy are spread out across the sky. While both of these measurements of dark matter mass are surprising, the systematic errors in these measurements are not well known. By studying the relationship between the assumptions made and the measurements obtained, the investigator will determine the range of dark matter masses of these Milky Way satellites that is consistent with currently available data.<br/><br/>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.
