01/22/2025
By Lynne Schaufenbil
Please join the Lowell Center for Space Science and Technology on Thursday, January 23 at 11 a.m. for a virtual talk by Chip Manchester
Abstract:
Coronal Mass Ejections (CMEs) are magnetically driven large-scale expulsions of plasma from the solar corona that travel through the heliosphere, and are the most significant drivers of geomagnetic storms. A presentation will be made of a history of large-scale numerical simulations of coronal mass ejections propagating past Earth's orbit. Early simulations modeled CMEs as density pulses and later employed magnetic flux ropes to produce eruptions with speeds more than 1000 km/s driving strong forward shocks through the solar wind and driving geomagnetic storms. The interaction of the CME with the solar wind causes perturbations to the wind that extend far beyond the ejecta and CME-driven shock waves and magnetic compressions, producing an environment very conducive to particle acceleration. Advances in coronal models based on synoptic magnetograms made it possible to model observed CME events with surprising fidelity. As an example, a model of the 2003, October 28 CME will be compared to observations, which shows remarkable agreement with LASCO coronagraph images. The forefront of simulation now strives to capture the energy buildup and release from two fundamental magnetic topologies, that of a preexisting magnetic flux rope or a sheared magnetic arcade. We show the latest examples being developed by the solar physics community.
Please email Lynne_Schaufenbil@uml.edu for the Zoom link if you are interested in attending.