STEREO Spacecraft Studies Extreme Space Weather

STEREO Spacecraft Studies Extreme Space Weather

On July 22, 2012, a massive cloud of solar material erupted off the sun's right side, zooming out into space and passing one of NASA's twin Solar Terrestrial Relations Observatory, or STEREO, spacecraft along the way. Scientists clocked this giant cloud, known as a coronal mass ejection, or CME, as traveling over 1,800 miles per second as it left the sun. This was the fastest CME ever observed by STEREO, which since its launch in 2006 has helped make CME speed measurements much more precise.