July 17th AR 1520-1521 CME, Come And Gone...

The above image is an artist's concept of the Advanced Composition Explorer (ACE) in space between Earth and the sun. Image Credit: NASA

A weak shock, driven by the July 17th coronal mass ejection (CME) from the sun's Active Regions 1520 and 1521 (AR 1520 and AR 1521) passed the Advanced Composition Explorer satellite (ACE) around 04:15 UTC (12:15 AM EDT) today (July 20th). ACE sits in space between Earth and the sun, in a halo orbit around the L1 Lagrange point. The CME has since passed Earth and caused no geomagnetic storm activity.

Back on the sun, the minor (S1) solar radiation storm persists, but should steadily decline through the day. AR 1520 and AR 1521 have now passed around the western limb of the sun. Elsewhere on the sun, And no significant activity has occurred at this time. Stay tuned...

To learn more about the Advanced Composition Explorer satellite (ACE) mission, visit www.srl.caltech.edu/ACE and science.nasa.gov/missions/ace .

To monitor solar flare activity minute by minute, visit the "Today's Space Weather" page of NOAA's Space Weather Prediction Center, URL: http://www.swpc.noaa.gov/ .

To learn more about the sun and to stay current on solar activity, visit the mission home pages of the Solar Dynamics Observatory (SDO), sdo.gsfc.nasa.gov and the Solar and Heliospheric Observatory (SOHO), sohowww.nascom.nasa.gov .

-