IRIS Movie of the Day
At least once a week a movie of the Sun taken by NASA's Interface Region Imaging Spectrograph (IRIS) is posted by one of the scientists operating the instrument.
Small flare with complex ribbons
Credit: IRIS, LMSAL/NASA, Arkadiusz Berlicki
The small but impressive B-class flare appeared in Active Region 12700 during the period of low solar activity. The slit crosses ribbons at their maximum brightness. Bright ribbons are visible due to the heating of the chromosphere by energetic particles accelerated in upper solar atmosphere and moving down along magnetic fields lines. At the beginning of IRIS movie, the complicated ribbons structure is visible suggesting the complex configuration of the magnetic field in this AR.