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.
Prominence dynamics and cavities
Credit: IRIS, LMSAL/NASA, Vanessa Polito
On May 19th, IRIS captured images and spectra of a beautiful prominence on the east solar limb. Prominences are giant columns of cool gas suspended in the hot solar corona, whose formation mechanisms remain elusive. In this observation, the high-resolution IRIS images reveal the presence of fascinating flow dynamics as well as empty dark areas called "cavities". Both features are key to understanding how prominences are formed and sometimes erupt, leading to the ejection of coronal material into the heliosphere.