Fast solar winds originating from the sun can have direct impacts on Earth – disrupting systems like GPS, aviation, electrical grids and satellite and radio communications. A new paper by New Mexico State University astronomy graduate student Khagendra Katuwal examines the connection between coronal holes and solar wind streams, helping improve our understanding of how the sun's magnetic structure influences space weather.
His paper "Unipolarity of the Solar Magnetic Field in Equatorial Coronal Holes" was recently published in The Astrophysical Journal.
"These findings help us better understand the magnetic conditions that produce high-speed solar wind streams from coronal holes," Katuwal said. "Because these fast solar wind streams can disturb Earth's magnetic environment, improving our knowledge of their origin helps scientists make more accurate space-weather forecasts."
Katuwal studied 70 coronal holes using data from the Solar Dynamics Observatory, a space-based telescope built to study solar activity, to better understand the origins of solar wind. He found that around 88% of the coronal holes studied showed a significant imbalance in their magnetic fields.
Regions on the sun that are more magnetically imbalanced can be linked to the formation of high-speed solar wind streams. By identifying changing magnetic conditions as an important factor in the formation of fast solar wind, his work helps strengthen space weather forecasting models and reduces the technological and economic risks to systems affected by the sun's activity.
Katuwal began researching coronal holes after taking a course on heliophysics, or the physics of the sun, taught by R.T. James McAteer, deputy provost and professor of astronomy. The class sparked Katuwal's interest in the sun, leading him to approach McAteer about opportunities for solar research projects.
"I chose to study coronal holes because they are believed to be the source of fast solar wind," Katuwal said. "I became fascinated by simple but fundamental questions. Is the solar wind we measure near Earth really coming from coronal holes? How does their magnetic structure produce this fast solar wind?"
"The biggest unknowns in trying to predict solar wind are in understanding how coronal holes form and how they stay 'open,' which means that the magnetic field lines from coronal holes connect out in space," McAteer said. "Regions with open field lines are unbalanced. Particles escape more easily, and so the solar wind will be fast and dense. Khagendra has created a set of parameters that now lets us define what we mean when we say 'unbalanced.'"
Next, Katuwal plans on using data from the Daniel K. Inouye Solar Telescope, the world's most powerful solar telescope, to study small features on the sun and learn more about what causes these regions to be unbalanced.
"Understanding the magnetic structure of coronal holes allows us to connect small-scale magnetic physics on the sun to large-scale space weather effects that impact our technology," he said. "That connection between fundamental physics and real-world impact strongly motivates me."
The full article can be seen at https://newsroom.nmsu.edu/news/nmsu-astronomy-student-s-research-on-coronal-holes-improves-space-weather-forecasting/s/bb3222af-0d64-4162-9ed2-8e159ac6a9c4
