The Sun Emits a Mid-level Flare and CME

The sun emitted a mid-level flare, peaking at 3:16 a.m. EDT on April 11, 2013.

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 disrupts the radio signals for as long as the flare is ongoing, anywhere from minutes to hours.

This flare is classified as an M6.5 flare, some ten times less powerful than the strongest flares, which are labeled X-class flares. M-class flares are the weakest flares that can still cause some space weather effects near Earth. This flare produced a radio blackout that has since subsided. The blackout was categorized as an R2 on a scale between R1 and R5 on NOAA's space weather scales.

This is the strongest flare seen so far in 2013. Increased numbers of flares are quite common at the moment, since the sun's normal 11-year activity cycle is ramping up toward solar maximum, which is expected in late 2013. Humans have tracked this solar cycle continuously since it was discovered, and it is normal for there to be many flares a day during the sun's peak activity.

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Scott Wiessinger (USRA): Producer
Karen Fox (ASI): Writer
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Data Used:
SOHO/Large Angle Spectrometric COronagraph (LASCO)/C3
SOHO/Large Angle Spectrometric COronagraph (LASCO)/C2
SDO/AIA/171 Filter
SDO/AIA/131 Filter

This item is part of this series:
Heliophysics Breaking News

Goddard TV Tape:
G2013-021 -- 2013 Heliophysics Breaking News

SVS >> Coronal Mass Ejection
SVS >> Solar Flare
SVS >> Solar Ultraviolet
SVS >> Sun
GCMD >> Earth Science >> Sun-earth Interactions
SVS >> Space Weather
SVS >> Solar Dynamics Observatory
SVS >> Heliophysics
NASA Science >> Sun

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version