University of Georgia faculty member Cassandra Hall is a co-principal investigator on a new project supported by $450,000 grant from the National Science Foundation to learn more about planetary formation by studying a star system over 500 light-years away. The grant funds a three-year collaborative research project between principal investigator New Mexico State University Astronomy Associate Professor Wladimir Lyra, co-principal investigator and Assistant Professor Cassandra Hall and NMSU astronomy Ph.D. student Eleanor Serviss. Their research focuses on a star known as AB Aurigae and the disk that surrounds it. Within this disk orbits the first, and currently the only, credible claim of a detection of a planet that formed via a method known as gravitational instability. "What's exciting to me about AB Aurigae is that we get to test a hypothesis,” Lyra said. “We still don't understand how planets form, but the AB Aurigae system matches most theoretical expectations of a long-debated process of planet formation. That's super interesting." AB Aurigae is a young Herbig Ae star in the Auriga constellation. It is located at a distance of approximately 509 light years from the Sun based on stellar parallax. A gas giant exoplanet that orbits an A-type star, AB Aurigae has a mass of 9 Jupiters and takes 587.7 years to complete one orbit of its star, and is 93.9 AU from its star. Its discovery was announced in 2022. "This is an amazing opportunity for us to figure out how planets form!" said Hall, assistant professor of computational astrophysicist in the Franklin College of Arts and Sciences department of physics and astronomy. "The AB Aurigae system is like a planet-formation laboratory that has been set up for us to test what happens when planets form rapidly through gravitational instability, rather than slowly over millions of years using core accretion. We can use our simulations to test against this incredible data, to figure out exactly what is really going on in that system." New Mexico State University announcement. Image: ALMA image of the dust ring (red) and gaseous spirals (blue) of the circumstellar disk AB Aurigae reveal gaseous spiral arms inside a wide dust gap, providing a hint of planet formation. By: Alan Flurry Type of News/Audience: News
