On July 29, 2006, SOHO observed a circular coronal mass ejection (CME) as it blasted out from the Sun. While not particularly large or strong as CMEs go, this cloud of particles maintained its distinctive shape as it passed out of the field of view of the coronagraph instrument. It does remind one of the Sun blowing a smoke ring, doesn't it? Smoke rings are examples of "vortex rings" (mushroom clouds are another). The video clip shows its progress over an entire day as it expands and becomes fainter. CMEs are large solar storms that erupt fairly frequently out from the Sun. They can carry a billion tons of matter at millions of miles per hour.

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.