What is this odd-looking extension that appeared on the Sun on September 22, 2006?

It is a solar prominence that does seem to be distinctly hook-shaped. Solar prominences are cooler clouds of gas that float above the solar surface. If one looks closely, one can see the wispy, leftover strands where it seems to have been attached somewhere further around near the edge of the Sun. At the time of this image, it has recently broken away from that point. Prominences are not very stable and quite often they do break away from the Sun when the magnetic forces that hold it in place become disrupted. It did not last long. Neither the previous image taken just six hours before this or the one taken six hours later show any sign of a filament. At about the time prominence this appeared, another instrument on SOHO observed a solar outburst called a "streamer" eruption near the same general area of this prominence.

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.