July 23, 2013
Coronal Mass Ejection Witnessed By NASA’s STEREO
On July 22, 2013, at 2:24 a.m. EDT, the sun erupted with a coronal mass ejection or CME, a solar phenomenon that can send billions of tons of solar particles into space that can affect electronic systems in satellites. Experimental NASA research models based on observations from NASA's Solar Terrestrial Relations Observatory, or STEREO, show that the CME was not Earth-directed, but may pass Mars.Â It left the sun at around 715 miles per second, which is a fairly fast speed for CMEs. The CME may also pass by NASA's STEREO-A spacecraft, and its mission operators have been notified. If warranted, operators can put spacecraft into safe mode to protect the instruments from the solar material.NOAA's Space Weather Prediction Center is the U.S. government's official source for space weather forecasts, alerts, watches and warnings.