An active region on the sun, numbered AR 1504, rotated into view over the left side of the sun on June 10, 2012. The region fired off two M-class flares and two coronal mass ejections (CMEs) on June 13 and June 14, 2012. The first flare lasted for a relatively long three hours, peaking on June 13, 2012 at 9:17 AM EDT. The associated CME traveled at approximately 375 miles per second and is directed toward Earth, though due to its slow speed, the effect on Earth is expected to be minimal.
The second M-class flare was also a long-duration flare, and it peaked on June 14, 2012 at 10:08 AM EDT. The CME associated with this flare is traveling much faster preliminary analysis at Goddard's Space Weather Center indicates it is traveling at speeds of approximately 800 miles per second. It is traveling toward Earth, and could also impact Mars and the Spitzer spacecraft.
The Space Weather Center models estimate that both CMEs will arrive on June 16.
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