quinta-feira, 11 de agosto de 2011

X 6.9 solar flare (partialy Earth-directed)

"With the sun moving to the peak of its 11-year solar cycle, today releasing the largest solar storm in years, NASA says the minor proton storm currently in progress around the planet is not Earth-directed. However, it is not ruling out a hit from another coronal mass ejection (CME) around 11 August so telecommunications might not be out of the woods yet in terms of disruption.

There had been concern the solar flares of recent days would affect telecoms, satellite and electric equipment this week, particularly in the wake of Friday's double-CME that hit the Earth's magnetic field, sparking a G4 category geomagnetic storm to the extent aurorae could be seen in northern latitudes.

Just today at 8.05am, sunspot 1263 produced a powerful X7-class solar flare, according to NASA. Its Solar Dynamics Observatory said this was the largest solar flare yet in the sun's current solar cycle.

There are three categories of solar flares: x-class flares are big and can trigger planet-wide radio blackouts and long-lasting radiation storms, says NASA. M-class flares are medium-sized and can cause brief radio blackouts that affect the Earth's polar regions. C-class flares are small and have few noticeable consequences for the planet.

"This flare had a GOES X-ray magnitude of X6.9, meaning it was more than three times larger than the previous largest flare of this solar cycle - the X2.2 that occurred on February 15, 2011," reported the Solar Dynamics Observatory today on the latest flare.

It captured the explosion's extreme ultraviolet flash. While the brunt of the explosion was not directed at planet Earth, NASA said today a minor proton storm is in progress around our planet, which could affect satellites in high-altitude orbits.

"Also, radiation from flares created waves of ionisation in Earth's upper atmosphere, briefly disrupting communications at some VLF and HF radio frequencies," reported Spaceweather.com today.

NASA - not ruling out disruption caused by CME on/around 11 August
NASA said SOHO coronagraphs show a CME emerging from the blast site.

"The cloud will probably miss Earth. At this time, however, we cannot rule out a glancing blow from the flank of the CME on or about August 11."

A solar flare as an explosion on the sun that happens when energy stored in twisted magnetic fields (usually above sunspots) is suddenly released, according to NASA. Massive bursts of solar wind, known as coronal mass ejections (CMEs), or 'solar burps' are associated with solar flares.

"The largest flare of the solar cycle, an R3 (Strong) Radio Blackout, alternatively classified as an X6, occurred today at 0805Z. Region 1263, now poised near the west limb, produced the event and a few others of lesser magnitude in the past day. The region remains hot at this writing. Given the location of the activity, any CMEs would likely be directed away from Earth so no significant geomagnetic storm activity is forecast," reported the NOAA/Space Weather Prediction Center this morning."

http://www.siliconrepublic.com/comms/item/23070-solar-storms-latest/

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