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

Over-achieving sunspot group 656 (August 19, 2004)

Hi-res TIF image (2.4M).

MPEG: Large (1.0M), Small (185K)
Quicktime: Large (1.3M), Small (204K)

Over a period of just five days, August 8-14, 2004, Active Region 656 went from a middling-sized group to a powerhouse with the area of nearly 20 Earths. The split screen Sun stills show how dramatically the group changed. Sunspots are areas of intense magnetic activity that can last from days to months and are always changing. Notice in the movie (over the longer period Aug. 8-16) that the Sun's rotation has moved the group from near the left side of the Sun most of the way around to the right side. This regular movement of sunspots was the first indication to observers on Earth that the Sun in fact rotated. Careful measurements showed that the rotation period of sunspots is about 27 days, though the visible surface of the Sun actually rotates a bit faster at the Sun's equator, and considerably slower near the solar poles.

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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Last modification: July 27, 2020

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