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Updated: Aug 13, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Observational aspects of sunspot oscillations
1High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO 80307, USA. tom@ucar.edu
Summary
Sunspot oscillations in umbrae and penumbrae are linked to thermal stratification and magnetic fields. These phenomena are interpreted as slow magneto-acoustic-gravity waves guided by the magnetic field.
Area of Science:
- Solar physics
- Plasma astrophysics
Background:
- Oscillatory phenomena are prevalent in the solar atmosphere.
- Sunspots exhibit unique magnetic field configurations and thermal properties.
Purpose of the Study:
- To review and critically discuss oscillatory phenomena in sunspot umbrae and penumbrae.
- To interpret these oscillations in the context of wave propagation.
Main Methods:
- Review of existing observational data and theoretical models.
- Analysis of the interplay between thermal stratification and magnetic collimation.
Main Results:
- Oscillations in sunspot umbrae and penumbrae are a natural consequence of atmospheric stratification and magnetic field effects.
- These oscillations are characterized as low-beta slow magneto-acoustic-gravity waves.
Conclusions:
- The observed oscillations provide evidence for wave guidance along the ambient magnetic field in sunspots.
- Understanding these waves is crucial for solar atmospheric dynamics.
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