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.
Sunspot with Light Bridge
Credit: IRIS, LMSAL/NASA, Tingyu Gou
Sunspots are dark, planet-sized areas that appear as temporary spots on the surface of the Sun. They have lower temperatures and much stronger magnetic fields than the surrounding areas. The IRIS movie shows part of a big sunspot in high-resolution, in the solar active region 13310 on 2023 May 22. An interesting feature is the light bridge that crosses the sunspot's dark umbra, which has an increased brightness and a higher temperature than in the surrounding umbra. In the other wavelength, the light bridge shows enhanced activities and dynamic behaviors with persistent jets and surges in the chromosphere, and umbral flashes and running penumbral waves are also very prominent. These phenomena provide important insights into the connection between the Sun's interior and the atmospheric layers.