A Hale of Solar Activity (June 24, 2004)
Hi-res TIF image (2.0M).
This comparison of still images shows how several significant sunspot groups are really visible evidence of the intense magnetic activity associated with them. The magnetogram (left) from 18 June 2004 shows several areas of magnetic intensity. The white and black areas indicate north and south polarity. Note that the leading and trailing spots in each group have opposite polarities in the northern and southern hemispheres. This polarity law was discovered by American astrophysicist George Ellery Hale, born June 29, 1868.
The orange Sun (right) shows what the Sun looks like in visible light, with the dark sunspots groups being the most noticeable features. Looking back and forth, one can readily identify the close correlation of active regions between the two kinds of images. Active regions with their intense magnetic activity are often the sites of solar storms.
The associated video clip shows the two types of images side-by-side for 11 days (June 10-20). Although the matching of the times of the images is not precise throughout the clip, the overall correlation holds up well. Some of the magnetic features don't show up as sunspots: these features remain after the spots decay or show us where new spots may be developing.
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 firstname.lastname@example.org.