New Insights into Solar Corona Heating
A recent study led by solar physicist Richard Morton has explored why the Sun’s outer atmosphere, the corona, is significantly hotter than its surface.
Temperature Discrepancy
- The Sun’s surface temperature, known as the photosphere, is approximately 10,000°F (5,500°C).
- The corona can reach temperatures of 2 million°F (1.1 million°C).
Role of Magnetic Waves
- The research focused on "magnetic waves" potentially responsible for this heating.
- Alfven waves are low-frequency, transverse electromagnetic waves along magnetic field lines.
- These waves had not been directly detected in the corona until this study.
Research Methodology
- Data was collected using the Daniel K. Inouye Solar Telescope (DKIST), the largest ground-based solar telescope.
- The Cryogenic Near Infrared Spectropolarimeter (Cryo-NIRSP) was used to study these waves.
- The Doppler shift effect was utilized to measure changes in solar plasma.
Findings and Implications
- The study confirmed the presence of Alfven waves through distinct Doppler shifts.
- These waves appeared as twisting patterns in the corona’s magnetic field.
- Alfven waves likely carry significant energy, playing a crucial role in coronal heating.
- Magnetic reconnection, previously believed to be a key mechanism, is now understood to occur alongside Alfven wave activity.
- Alfven waves may provide at least half of the energy required for coronal heating.
Broader Implications
- The study aids in understanding solar dynamics and predicting solar radiative output.
- These findings have implications for understanding planetary system evolution and improving solar wind forecasts.
Future Research
- Future studies aim to further explore Alfven waves’ characteristics.
- Results could refine current models and predictions regarding solar behavior.