"Dynamics of Solar Wind Outflow"

The Physics Department welcomes Dr. Yeimy Rivera as our final speaker in our 2023-2024 Seminar Speaker Series!

4:30pm Snacks, 4:45pm Talk

In the corona of the Sun, plasma is accelerated to speeds of hundreds of kilometers per second and heated to temperatures hundreds of times hotter than the Sun's surface before it escapes to form the solar wind. Decades of space-based experiments have shown that the energization process does not stop after it escapes. Instead, as the solar wind fills interplanetary space it continues to accelerate, while cooling far more slowly than a freely expanding adiabatic gas would. This talk will discuss observations of a well-timed conjunction between two solar probes, NASA’s Parker Solar Probe and ESA’s Solar Orbiter, where we examine the large-scale energetics of a moderately fast, highly Alfvénic solar wind stream across the inner heliosphere, observed from 13 solar radii to nearly the orbit of Venus (155 solar radii). Observations of the solar wind taken by the two probes across this region of space strongly support the hypothesis that large amplitude Alfvén waves are the engine heating and accelerating the fastest solar wind beyond the corona.

Dr. Yeimy Rivera is a solar astrophysicist at the Smithsonian Astrophysical Observatory. She received her PhD at the University of Michigan in Space Physics. Her research pertains to understanding how the Sun generates the continuous outflow of solar wind and how it influences interplanetary space and the solar system. She is part of NASA’s Parker Solar Probe and European Space Agency’s Solar Orbiter team. She is the Deputy Project Scientist for future solar telescope – EUV CME and Coronal Connectivity Observatory (ECCCO), and Project Scientist for the Airborne Coronal Emission Surveyor (ACES) 2024 eclipse mission.