Large prominence
This EIT full sun image in the He II emission line at 304 A shows the upper chromosphere/lower transition region at a temperature of about 60,000 K. Note the large prominence at the north-west limb (upper right) and the erupting prominence at the east limb (left). These eruptions occur when a significant amount of cool dense plasma or ionized gas escapes from the normally closed, confining, low-level magnetic fields of the Sun's atmosphere to streak out into the interplanetary medium, or heliosphere. Eruptions of this sort can produce major disruptions in the near Earth environment, affecting communications, navigation systems and even power grids. SOHO, with its uninterrupted view of the Sun, can observe such events continually, and allow us for the first time to get a better understanding of how such violent events occur.