
The STEREO (Ahead) spacecraft observed this visually stunning prominence eruption on Sept. 29, 2008 in the 304 wavelength of extreme UV light. It rose up and cascaded to the right over several hours, appearing something like a flag unfurling, as it broke apart and headed into space. The material observed is actually ionized Helium at about 60,000 degrees. Prominences are relatively cool clouds of gas suspended above the sun and controlled by magnetic forces.
NASA's twin STEREO spacecraft are offering the first glimpse of the far side of the sun, the space agency announced today.
The two spacecraft, launched Oct. 25, 2006, are beaming back over-the-horizon images "that have researchers and forecasters glued to their monitors," according to a statement.
"This is a perspective we've never had before," says STEREO mission scientist Lika Guhathakurta of NASA headquarters. "We're now monitoring more than 270 degrees of solar longitude - that's 3/4ths of the star."










