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IWannaKnow
02-15-2011, 10:01 AM
http://www.msnbc.msn.com/id/41587712/ns/technology_and_science-space/?gt1=43001

Earth 'in the crosshairs' of a solar explosion
Powerful flare hurled from sun might create great display of northern lights

By Joe Rao
Space.com
updated 2/14/2011 5:43:21 PM ET 2011-02-14T22:43:21

The sun unleashed the solar flare yesterday at about 12:30 p.m. EST from a sunspot region that was barely visible last week. Since then, it has grown in size to more than 62,000 miles across nearly eight times the width of our Earth.

The flare was categorized by the NOAA Space Weather Prediction Center in Colorado as a Class M6.6 and is the strongest solar flare observed in 2011. It could ramp up northern lights displays for skywatchers living in northern latitudes and graced with clear skies.

Such a flare, covering more than 1 billion square miles of the sun's surface (called the photosphere), was described as "moderate" in intensity. Class M flares are stronger than the weakest category (Class C). They are second only to the most intense Class X solar flares, which can cause disruptions to satellites and communications systems and pose a hazard to astronauts in space.
NOAA's Prediction Center has forecast the possibility of additional solar flares from the same sunspot region over the next two or three days.

However, Sunday's solar flare occurred near the middle of the sun's disk, meaning that the resultant explosion of electrified particles could be "geoeffective," that is, directed toward the Earth.

So, in essence, our planet was "in the crosshairs" of this solar explosion and would thus increase the chance that an auroral display might result. Ideally, the associated stream of particles could reach the Earth 37 hours after the flare's eruption.

That would correspond Tuesday, Feb. 15, at about 1:30 a.m. EST. But this is only an approximation; the actual commencement of a possible magnetic storm could occur many hours earlier or later, so it would be best to check the sky periodically during the overnight hours to assess if any activity is actually taking place.