After an unusually long period of quiescence, the Sun's activity started ramping up last summer.

February 15th's solar flare

Left: A cluster of sunspots marks Active Region 1158, which unleashed a powerful flare on February 15, 2010. Click here for an enlarged view. Right: A closeup of the flare, taken in the 335-angstrom (extreme-ultraviolet) emission of highly ionized iron, corresponding to temperatures of 2,200,000 K (4,000,000°F).

Now sunspot group 1158 has unleashed a series of blasts culminating with an X2 flare at 1:56 UT February 15th (8:56 p.m. EST on the 14th). This is the strongest solar eruption in four years, and the impressive coronal mass ejection that accompanied it dealt a glancing blow to Earth's magnetic field three days later. The impact was smaller than expected, and only caused northern lights (or auroras, as scientists call them) in the deep arctic.

However, this flare is a clear indication that solar activity is on the increase, so observers at moderate to high latitudes should stay tuned to the aurora forecasts and keep their eyes open for unexpected auroras. And solar observers have a new, large sunspot group to watch — one that's readily visible in properly filtered binoculars. (Experienced observers don't need this warning, but you must NEVER look at the Sun without a filter specifically designed for this purpose. )

For more information on this flare, auroras — and solar activity in general — see


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robert schneider

February 18, 2011 at 11:16 am

the flanders article confused me. the earth impact date was given as 18 feb however other websites were a day earlier. the article suggested nothing notable but northern lights however the BBC reported large electrical outages in parts of china. nasa posted warnings.

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terry swann

March 8, 2011 at 2:13 am

Various sites like Spaceweather, and other news sources put out the news about an M2 class solar flare around 15hrs Z.
Now I know there won't be an aurora around Hawaii, but..

ANYONE know a good source of arguments, blogs, or other editorials about the upcoming new solar cycle, which was delayed by slowing plasma rivers on Sol during the extra long minimum,? ? I'm trying to help a friend debunk anything that makes this cycle more alarming than 1917? Solar minimum, the Maunder minimum, and Brand new variables about our Variable G class star. Bueller? Bueller ?

Especially looking for speculators, fanatacists, and doom - sayers, regarding the Web, internet, satellites, GPS , ISS, Ozone and Cosmic ray protection loss, and power grids. At least AFAIK, there's not much "balogna" about earth's pole shifts and magnetic field reversals. Sun does plenty of that for itself, i guess. Terry from Maui.
(Below the tropic of "Taurus?" Barely. Happy skies.
Not much chance of an aurora here. .

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