Solar prominence. SOHO images showing the expansion of a solar prominence over the course of 18 hours. A prominence is a cloud of plasma in the corona of the Sun. From top left, the times are: 19:18 on 19th May 2000, 01:18 on 20th May, 07:18 (lower left) and finally 13:18 on 20th May 2000 at bottom right. The prominence is shaped by the curved magnetic field lines around the Sun's surface. Images taken by the Extreme Ultraviolet Imaging Telescope (EIT) on board the SOHO (Solar and Heliospheric Observatory) spacecraft.