Bright Grains in the Chromosphere of the Sun

• 16 Jun 2023

Recently, a new study has found that bright grains observed in the chromosphere of the Sun are due to upward propagating shocks in the solar plasma.

Key Findings of the Study

• Bright Grains in the Chromosphere: The study identifies upward propagating shocks in the solar plasma as the cause of bright grains observed in the chromosphere of the Sun.
• Higher Temperature Enhancements: The research reveals that the temperature enhancements during acoustic shock events in the chromosphere are higher than previous estimates.
• Average Temperature Rise: On average, the temperature can increase by approximately 1100 K during acoustic shocks, with a maximum increase of about 4500 K, which is three times higher than earlier studies.
• Predominant Upward Motion: The atmospheric layers experiencing temperature enhancement predominantly move upwards during acoustic shocks.
• Data Sources and Analysis: High-quality observations of grains from the Swedish Solar Telescope were used, along with the state-of-the-art inversion code called STiC, running on a supercomputer provided by the Indian Institute of Astrophysics (IIA).
• Machine Learning Optimization: Machine learning techniques were employed to optimize the inversion process, significantly speeding up the computation of the observational data.
• Chromospheric Heating Mechanism: Acoustic shocks, caused by sound waves from lower altitudes, contribute to heating the chromosphere by increasing its plasma density.
• Significant Temperature Enhancements: The temperature enhancements calculated in the study are 3-5 times greater than previous estimates.
• Support for Upflowing Plasma Interpretation: The research findings support earlier studies suggesting that the temperature enhancements observed during acoustic shocks are due to upflowing plasma.