Our Sun

Postcard courtesy of SOHO/EIT/NASA.

Caption: This EIT full sun image, taken in the He II emission line at 304 A shows the upper chromosphere/lower transition region at a temperature of about 60,000 K. The bright features are called active regions. A huge erupting prominence escaping the Sun can be seen in the upper right part of the image. Prominences are "cool" 60,000 K plasma embedded in the much hotter surrounding corona.