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.
A Microflare and the South Atlantic Anomaly
Credit: IRIS, LMSAL/NASA, Magnus Woods
In this movie we see what is called a microflare. Microflares, like larger solar flares are very fast releases of magnetic energy into the atmosphere of the Sun. Although they release much less energy than their larger cousins they are still an incredibly energetic and beautiful phenomena! At the end of the movie we can also see lots of speckled features across the whole field of view. This is caused by a large number of particles and radiation hitting IRIS's detector as it passes through a region called the South Atlantic Anomaly (SAA) on its orbit around the Earth. The SAA is the result of the Earth's Inner Van Allen Radiation Belt being closest to the surface in this area, with an altitude of roughly 200 km.