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.
Unraveling a Giant Pillar of Plasma on the Sun
Credit: IRIS, LMSAL/NASA, Chad Madsen, SAO
This is an observation of a towering arch structure known as a prominence. These behemoths are the result of magnetic fields dredging up cool plasma from the lower layers of the solar atmosphere and then suspending it into the hot corona above. How exactly this happens is still an open question in solar physics. Even more mysteriously, prominences have a habit of unexpectedly detaching from the Sun and flying off into interplanetary space, an event known as a prominence eruption. IRIS was lucky enough to capture this prominence eruption off the eastern limb of the Sun. At first, the prominence appears as a huge pillar looming tall over the Sun; the prominence is so huge that IRIS can only capture the base of the archway! Without warning, the enormous column of plasma then becomes unstable and appears to unravel into flat sheet, sailing away from the Sun with urgency and a bit of grace.