Strongest Solar Flares in Decade

The sun emitted a significant solar flare, peaking at 12:06 p.m. EDT on Sept. 10, 2017. NASA’s Solar Dynamics Observatory, which observes the sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel.

This flare is classified as an X8.2-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

This flare is the capstone on a series of flares from Active Region 2673, which was identified on Aug. 29 and is currently rotating off the front of the sun as part of our star’s normal rotation.

Of the two solar flares, the second was the strongest observed since 2008. Global communications and some GPS systems were temporarily affected on the sunny side of the Earth at the time. The first flare, which peaked at approximately 5:10am EDT, was classified as an X2.2.

The radio “blackout period” caused by the storm has already passed, affecting some high frequency radio and GPS communications for approximately one hour on the sunlit side of the Earth at the time of the event.

X-class solar flares are the largest explosions that take place within our solar system, shooting out jets of plasma that can reach up to 10 times the size of the Earth in length.
For reference, the most powerful solar flare ever recorded took place in 2003 and was measured as an X28, the New Scientist reports.

To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

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References

NASA. (2017). Sun Erupts With Significant Flare. [online] Available at: https://www.nasa.gov/feature/goddard/2017/active-region-on-sun-continues-to-emit-solar-flares [Accessed 13 Sep. 2017].

RT International. (2017). Monster belches: Sun produces most powerful solar flare in over decade (PHOTOS). [online] Available at: https://www.rt.com/news/402247-powerful-solar-flares-nasa/ [Accessed 13 Sep. 2017].