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Moderate Geomagnetic Storm at Earth
03.12.12
 
UPDATE 03/12/2012

Geomagnetic storms at Earth are currently at a rating of G2 (moderate) on a scale of G1 to G5. This is due to the arrival of a coronal mass ejection that began at 1 p.m. EST on March 10, 2012, in association with the two M-class flares that day. Storms at this rating may have an effect on high frequency radio communications at high latitudes and may cause increased aurora.



UPDATE 03/10/2012

Our sun at 12:29pm EST on March 10, 2012, inextreme ultraviolet wavelength.
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This image was captured by the Solar Dynamics Observatory (SDO) on March 10, 2012 at 12:29PM EST in the 304 Angstrom wavelength. An active region on the sun, seen above as the bright spot to the right, has been moving across the face of the sun from left to right since March 2, 2012. Designated AR 1429, the spot has so far produced three X-class flares and numerous M-class flares.Credit: NASA/SDO/AIA


On March 10, 2012, the sun released another two M-class flares. One, rated as an M5.4, peaked at 12:27 AM EST. The second, rated as an M 8.4, peaked at 12:44 PM EST.

These two flares came from the same Active Region (AR) on the sun, designated number 1429, that has already produced three X-class and numerous M-class flares over the past week.



SOHO captured these three images showing the evolution of the CME.
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SOHO image caption: These three images show the evolution of the coronal mass ejection from March 8, 11:38 PM EST to March 9, 12:53 AM EST as captured by the Solar Heliospheric Observatory (SOHO). The sun is obscured in this image, called a coronograph, so that the dim atmosphere -- or corona -- around the sun can be better seen. The white speckles on the image are “noise” from solar particles hitting the instrument. Credit: SOHO/ESA & NASA


Active sunspot region 1429 continues to grow, currently measuring more than seven times wider than Earth. Sunspot 1429 continues to grow and may yet produce more flares. It is now more than seven times wider than Earth Credit: NASA/SDO/HMI
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On March 8, 2012 at 10:53 PM EST the sun erupted with an M6.3 class flare, and about an hour later released a coronal mass ejection (CME). These eruptions came from active region 1429 that has so far produced two X class flares, and numerous M-class flares.

NASA's Space Weather Center models measure the CME traveling at speeds of over 700 miles per second. The CME should reach Earth's magnetosphere, the protective envelope of magnetic fields around the planet, early in the morning of March 11.

More news and media to come as it becomes available.


What is a solar flare? What is a coronal mass ejection?

For answers to these and other space weather questions, please visit the Spaceweather Frequently Asked Questions page.
 
 
Karen C. Fox
NASA Goddard Space Flight Center, Greenbelt, Md.