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 eruptive flare
Credit: IRIS, LMSAL/NASA, Vanessa Polito
Although approaching a period of solar minimum, the Sun can still be very dynamic. This video shows a small "eruptive" B-class flare which was observed by IRIS on 04/10/2019. Flares are widely believed to be triggered by reconnection of magnetic field lines in the solar atmosphere. In this video, we can see a large arc of magnetized plasma (so-called "filament") which rapidly rises and breaks open, releasing plasma material into the heliosphere. The filament, as well as the bright flare ribbons, are observed by the IRIS spectrograph slit.