Over a two-day period (Aug. 19-21), 2006) a SOHO coronagraph observed three coronal mass ejections blasting into space, a level of activity we have not seen for some time. (There was also a minor fourth CME on the other side of the Sun late on the 21st.) The still image shows the second storm leaving the field of view and the third storm (above it) just emerging from behind the red occulting disk.

The culprit responsible for these storms appears to be Active Region 904, a large sunspot group that had just about completed its rotation across the Sun (at least from the Earth's and SOHO's perspective). (See the previous Pick of the Week.)

CME's occur when the intense magnetic forces above a sunspot group rip apart, sending a billion tons of matter into space at millions of miles per hour. Since the Sun is near its minimum period of activity in the solar cycle, these solar storms are not so common.

Previous Picks of the Week

SOHO began its Weekly Pick some time after sending a weekly image or video clip to the American Museum of Natural History (Rose Center) in New York City. There, the SOHO Weekly Pick is displayed with some annotations on a large plasma display.

If your institution would also like to receive the same Weekly Pick from us for display (usually in Photoshop or QuickTime format), please send your inquiry to steele.hill@gsfc.nasa.gov.