07 February 2023 - Mission Day: 9930 - DOY: 038
Pick of The Week

First Sunspot of New Solar Cycle (January 9, 2008)

Hi-res TIF image (1.0M)

Hi-res TIF image (3.6M)

MPEG Movie: Large (3.9M)
Quicktime Movie: Large ( 11M), Small (925K)
Difference movie (2.0M)

Which magnetic polarity leads and which follows in solar active regions alternates with each, roughly 11.1 year solar activity cycle (and is opposite in the Sun's northern and southern hemispheres). Thus the first active region with opposite ordering of polarities is recognized as the harbinger of a new solar cycle. Cycle 24 began last week, when it was officially confirmed on January 4, 2008, that SOHO observed the first "reversed" sunspot of the new solar cycle, something scientists have been seeking for about a year. On that day, the fairly petite active region was officially classified as an active region by NOAA (AR 10981). Since it appeared at a high solar latitude and its magnetic orientation is opposite of the last solar cycle, scientists were convinced that Solar Cycle 24 has begun.

Hi-res TIF image (848K)

But not only did it appear, it generated two EIT waves, a kind of solar storm that blasts out from an active region across a portion of the Sun's surface. The video clip (covering about 24 hours) in extreme UV light shows the first, smaller wave on January 6, and a stronger wave the next day. A second clip shows the same events as a running difference movie, in which the differences between one frame and the next are highlighted so that changes can be more easily seen. So the cycle is starting out with a bit of a bang to it. However, this is just the beginning and solar activity will increase slowly over the next few years until it reaches another maximum predicted to occur in 2011 or 2012.

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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