The Unquiet Sun Target Name:   Sun Spacecraft:   SOHO Produced by:   ESA/NASA Copyright:  Public Domain Cross Reference:   None

• Sun

This sequence of images of the the Sun in ultraviolet light was taken by the Solar and Heliospheric Observatory (SOHO) spacecraft on Feb. 11, 1996 from its unique vantage point at the "L1" gravity neutral point 1 million miles sunward from the Earth. An "eruptive prominence" or blob of 60,000-degree gas, over 80,000 miles long, was ejected at a speed of at least 15,000 miles per hour. The gaseous blob is shown to the left in each image. 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. SOHO is observing these events during the current minimum phase of the sun's 11-year activity cycle. The images were obtained at wavelengths absorbed by the Earth's atmosphere by the Extreme ultraviolet Imaging Telescope.

SOHO is a project of international cooperation between NASA and the European Space Agency. The spacecraft was launched by NASA Dec. 2, 1996 from Cape Canaveral Air Station in Florida. Science operations for the SOHO spacecraft are being conducted by a NASA-ESA team from the Experiment Operations Facility at the Goddard Space Flight Center in Greenbelt, Maryland.