On May 13, 2013, the sun emitted an X2.8-class flare, peaking at 12:05 p.m. EDT. This is the the strongest X-class flare of 2013 so far, surpassing in strength the X1.7-class flare that occurred 14 hours earlier. It is the 16th X-class flare of the current solar cycle and the third-largest flare of that cycle. The second-strongest was an X5.4 event on March 7, 2012. The strongest was an X6.9 on Aug. 9, 2011.
On May 12, 2013, the sun emitted a significant solar flare, peaking at 10 p.m. EDT. This flare is classified as an X1.7, making it the first X-class flare of 2013. The flare was also associated with another solar phenomenon, called a coronal mass ejection (CME) that can send solar material out into space. This CME was not Earth-directed.
The May 12 flare was also associated with a coronal mass ejection, another solar phenomenon that can send billions of tons of solar particles into space, which can affect electronic systems in satellites and on the ground. Experimental NASA research models show that the CME left the sun at 745 miles per second and is not Earth-directed, however its flank may pass by the STEREO-B and Spitzer spacecraft, and their mission operators have been notified. If warranted, operators can put spacecraft into safe mode to protect the instruments from solar material. There is some particle radiation associated with this event, which is what can concern operators of interplanetary spacecraft since the particles can trip computer electronics on board.
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 8.0.0.0.0