Sun Unleashes 5 Major Flares, Earth May Soon Get Pounded

Space.com
Sep. 10, 2005

An ongoing series of major solar flares, including one late Friday, could disrupt communications on Earth and generate colorful sky shows for people at high northern latitudes over the weekend.

Even more serious effects are possible next week.

The spate of activity from the Sun is being generated by a large sunspot named 798. Sunspots are cooler and darker regions of pent-up magnetic activity. When they unleash their energy, it's a bit like the top coming off a shaken champagne bottle.

Solar flares send radiation to Earth in about 8 minutes. Hours later, clouds of charged particles can engulf the planet. If the magnetic field of a storm is oriented opposite to our planet's protective magnetic field, gaps are created and radiation leaks to the planet's surface, potentially threatening astronauts aboard the International Space Station, sometimes shorting out satellites, and even causing terrestrial power grids to trip.

Solar activity is at "very high levels," according to NOAA's Space Environment Center (SEC).

There have been five major flares in recent days, including a tremendous X-17 eruption Wednesday. The most recent event Friday evening was an X-6. Even an X-1 can cause severe disruptions.

The largest flare in modern times was recorded in November 2003 and was estimated to be an X-40. It, too, was on the limb of the Sun and so its full impact was not felt on Earth. That flare was part of an unprecedented series of 10 major flares within two weeks.

Each storm is different, and often solar activity goes unnoticed on Earth, depending on whether a storm hits us square or makes a glancing blow and what the magnetic orientation is.

If enough storms erupt, the odds go up that there will be effects here.

There is a 75 percent chance of more X-class flares through Monday, the SEC says.

The sunspot is just rotating into view, so its energy has been directed sideways and not directly at Earth. In coming days, if more major flares erupt, they'll head right at us and radio blackouts, cell phone dropouts and other communications disruptions are more likely, scientists said.

On Friday, a space radiation storm was captured in an image from the SOHO spacecraft, which monitors the Sun.

The Sun is currently at a low point in its 11-year cycle of activity. While sunspots and flares are less common now, astronomers say they can pack plenty of punch when they do occur.

* Live Sun Cam
* Speed Limit Found For Solar Storms
* Key to Solar Storms Found, Better Forecasts Expected
* The Great Storm: Solar Tempest of 1859 Revealed
* Mysteries of the Sun