Aurora Over Quebec
Auroras create green curtains of light August 4 over the Rupert River in Waskaganish (see map), a Cree Nation community in Quebec, Canada.
Last week's northern lights—which lasted a few days—were products of a large burst of plasma, or charged gas, from the sun known as a coronal mass ejection. A NASA orbiter called the Solar Dynamics Observatory saw last Sunday's eruption, which was aimed directly at Earth and sparked predictions of a shimmering sky show.
Now it seems aurora fans may be in for another treat: A solar flare spotted Saturday by NASA's Solar and Heliospheric Observatory was even more powerful than the previous eruption. Although this time the bulk of the plasma burst isn't aimed right at Earth, scientists say it could still trigger another round of colorful auroras.
Pictures: Huge Solar Storm Triggers Unusual Auroras
See some of the colorful auroras triggered by last week's huge coronal mass ejection, which brought the sky show farther south than normal.