GSA Today
Volume 29, Issue 12

Cover image

Composite of two images, one of the solar corona as seen during the total solar eclipse of 21 Aug. 2017, the other of the solar disk at ultraviolet frequencies as imaged by the Solar Dynamics Observa-tory satellite. Streamers from polar regions are areas where solar wind f lows outward along magnetic field lines. At lower solar latitudes, arcing magnetic-field lines are associated with sunspots and other surface activity that can yield explosive coronal mass ejections. Both solar wind and mass ejections carry away mass and angular momentum. This type of solar activity was much greater during the Sun’s fast-spinning youth. Image provided by Miloslav Druckmüller, Institute of Mathematics, Faculty of Mechanical Engineering, Brno University of Technology, Czech Republic.

https://doi.org/10.1130/GSATG403A.1

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