The sun is active again. A very large sun spot has rotated around the sun and is now about to face directly toward the Earth.
This sun spot, known as AR1476, burped out a pair of solar eruptions on May 7 and hurled coronal mass ejections (CMEs) toward Earth.
CMEs are massive bursts of solar wind and magnetic fields. Coronal mass ejections release huge quantities of matter and electromagnetic radiation into space. The ejected material is a plasma, consisting mainly of protons and electrons. They also contain small quantities of helium, oxygen and even iron. These bursts of energy strike the Earth's magnetic field, causing colorful auroras or, worse, major disruptions to the world's electrical grid.
Forecast tracks prepared by analysts at the Goddard Space Weather Lab suggests that clouds will arrive in succession on May 9 at 9:40 a.m. EDT and May 10 at 4:00 am EDT (+/- 7 hours). The double impact could spark moderate geomagnetic storms. Sky watchers should be alert for auroras.
With a least four dark cores larger than Earth, AR1476 sprawls more than 100,000 km from end to end, and makes an easy target for backyard solar telescopes.
"AR1476 is firecracker," said amateur astronomer Alan Friedman Friedman, from Buffalo NY., who has been watching this sunspot since the weekend.
Indeed, the active region is crackling with impulsive M-class solar flares. Based on the sunspot's complex "beta-gamma" magnetic field, NOAA forecasters estimate a 75 percent chance of more M-flares (moderate energy bursts) during the next 24 hours. There is also a 10 percent chance of powerful X-flares (extreme energy bursts).
"This one is going to be fun as it turns to face us," predicts Friedman. He might be right.