The Not So Quiet Sun

After a long solar minimum , the Sun is no longer so quiet . On August 1, this extreme ultraviolet snapshot of the Sun from the Solar Dynamics Observatory captured a complex burst of activity playing across the Sun's northern hemisphere. The false-color image shows the hot solar plasma at temperatures ranging from 1 to 2 million kelvins . Along with the erupting filaments and prominences, a small(!) solar flare spawned in the active region at the left was accompanied by a coronal mass ejection ( CME ), a billion-ton cloud of energetic particles headed for planet Earth. Making the 93 million mile trip in only two days, the CME impacted Earth's magnetosphere , triggering a geomagnetic storm and both northern and southern auroral displays.