CAREER: Evolution of Stream Interaction Regions from 1 to 5.4 AU and the Implications for Geomagnetically Induced Currents

Montana State University, Bozeman MT

Investigators

Abstract

This CAREER project focuses on Stream Interaction Regions (SIRs), and their implications for producing geomagnetic induced currents (GICs) on Earth. SIRs are formed when the fast solar wind interacts with the slow solar wind in front of it, creating a magnetic compression region (which may or may not form a shock). These compression regions are efficient particle accelerators and can initiate geomagnetic storms. These SIRs also can cause geomagnetic induced currents, which are measured by ground-based magnetometers. The project will integrate this work with educational outreach by starting the Space Weather UnderGround program that creates curriculum resources for high school teachers and puts scientific equipment in the classroom, beneficial to both students and scientists. Additionally, to increase public understanding of space weather, the PI will create a class called “The Sun and Society” to meet the natural sciences requirement at Montana State. The PI is an early career female faculty member in an EPSCoR state and the project is interdisciplinary and co-funded by the Solar-Terrestrial Research and Magnetospheric Physics programs. To better understand how SIRs evolve as a function of radial distance this project will answer the following science questions: (1) How do compressions (often but not always shocks) associated with SIRs/CIRs steepen between 1 au and 5.4 au? How do these compressional changes relate to the co-located particle populations? (2) How do the compression ratios, density ratios, and onset timing, as predicted by the WSA- ENLIL model as run by the NSF/NASA supported Community Coordinated Modeling Center (CCMC), compare to the observed data at Maven and Juno? (3) Is there a direct relationship between the compression ratio of a SIR and if there is a dB/dt (a GIC proxy) signal? This proposal will use data from NASA spacecraft near Earth, near Mars, and then a spacecraft as it was on its way to Jupiter to understand the radial evolution and co-located particles. The PI will link the compression ratios to how strong of GICs they can produce and at what latitudes. This effort will require the CCMC to forecast the arrival times of the SIRs at the various spacecraft. Finally, the project will use data from SuperMAG to link the SIR-induced GICs to their compressional strength and look for latitudinal dependencies. 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.