Omomyid and other readers send in the news that the bright flash of an impact on Jupiter
has been observed — and caught on film
— by amateur astronomers. That WMV is from amateur Christopher Go. Here's Anthony Wesley's video
(45 MB AVI; the site is already overloaded). In the larger video you can see the impact lasting for a couple of seconds, and a good deal of structure is visible. The amateurs report that no dark debris field developed around the impact site in the time before it rotated out of sight; this may indicate that the impactor burned up high in Jupiter's atmosphere. Soon professional astronomers, and possibly Hubble, will be on the job.