Hmmm. One of Jupiter’s most prominent dark bands, the South Equatorial Belt or SEB, has essentially disappeared over the last year. You can see the before and after pictures in this entry at the Planetary Society’s blog. Apparently this is something that happens on a somewhat regular basis, generally every 3 to 15 years. I try to keep up-to-date on amateur astronomy so I was somewhat surprised that I can’t remember hearing about this before. Maybe I did but my memory is just going bad. Anyway you can also check out this post by Astro Bob (also linked to from the Planetary Society blog post) to get much more explanation about what astronomers think is going on in Jupiter’s atmosphere.
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