12 June 2024 - Mission Day: 10421 - DOY: 164
Pick of The Week

Surf the Wave (November 4, 2004)

Hi-res TIF image (2.5M).

large (MPEG,1.6M), small (MPEG,572K)
large (QT,1.5M), small (QT,303K),

On Nov. 3, 2004 two M-class or moderate solar flares erupted from Active Region 696. What is unusual about these events is that the magnetic instability that led to them also triggered pulses that swept across a substantial area of the Sun's surface. This motion, like a tidal wave, is called a Moreton wave, a relatively rare event. Though the waves are somewhat subtle, they can be observed about 3/4 of the way through the extreme ultraviolet movie from SOHO as it expands across the upper portion of the Sun. To generate enough force to travel such distances of hundreds of thousands of miles across the surface of the Sun --- and hundreds of millions of km the associated coronal mass ejection travels across the solar system --- suggests the enormous magnetic energy release that triggers such a storm in the first place. The movie shows just the one day.

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.


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