Discovery Foretells Harmful Solar Blasts

Fiery “S” shapes on the Sun’s surface can help predict when potentially dangerous and disruptive blasts of electrically charged gas will come hurtling toward Earth, scientists said. Such massive solar explosions pack the force of billions of nuclear blasts and can knock out power grids, damage satellites and scramble communications networks. The discovery of the telltale shape means forecasters can detect the blast even before it happens, giving Earth up to six days to get ready. The shapes, called sigmoids, were glimpsed by the Japanese Yohkoh spacecraft and explained at a NASA briefing in Washington.