'Monster sunspot' may foretell powerful solar flares, says NASA

The huge sunspot complex, known as AR 1476, rotated into Earth’s view over the weekend. It measures more than 60,000 miles (100,000 kilometers) across, researchers said. Scientists with NASA’s Solar Dynamics Observatory mission, a space-based telescope watching the sun, dubbed the solar structure a “monster sunspot” in a Twitter announcement. AR 1476 is big enough for amateur astronomers with decent equipment to spot from their backyards, weather permitting. Sunspots are temporary dark patches on the surface of the sun that are caused by intense magnetic activity. These structures sometimes erupt into solar flares, which send high-energy radiation streaming into space. Solar physicists classify flares into three main categories: C, M and X, with C being the least powerful and X the strongest. X-class flares can cause long-lasting radiation storms in Earth’s upper atmosphere and trigger radio blackouts. M-class flares can cause brief radio blackouts in the polar regions and occasional minor radiation storms, while C flares have few noticeable consequences. AR 1476 has already proven quite active, firing off a number of C flares over the past few days. And another sunspot group, AR 1471, erupted Monday evening with one that seems to be an M1, one of the least powerful M flares.