I had very much hoped to be able to post an update about the Deep Impact mission this week, but it looks like my various sources are keeping very very quiet (or maybe they are just tired of me pestering them :)
In short, there is no crater diameter to report yet; I'm sorry to disappoint all of you who are writing in to ask if you won our Great Comet Crater Contest. But don't despair. Sooner or later, some information will come out. I do very strongly suspect -- and this is just personal opinion here -- that that information is more likely to be a range of possible crater diameters than it is to be a specific diameter plus or minus a few meters.
What does that mean for the outcome of the contest? We've discussed that here at The Planetary Society, and decided that, probably, if they report a range for the possible crater diameter, we'll use that range to select a pool of potential winners from the thousands of entries we received, and then select randomly from that to award prizes. I just did an interview with a guy from National Public Radio about this today, and his remark was "somehow that's just not very satisfying." Very true. But the real point of all of this is that Deep Impact was a mission designed to teach us stuff we didn't know about comets. Guess what? Scientists didn't know that there would be so much dust tossed up from the impact that they wouldn't be able to see the crater. So, we learned something! One of the philosophies that I hear frequently from scientists is that "if we could predict exactly what was going to happen, there'd be no point in the mission, would there?"
Fair enough, you may say, but when are we going to find out who won? And seriously, why is the mission team keeping its collective mouth so tightly closed? There are two answers. One: they are preparing, or may have submitted by now, a set of papers to Science. Those two grand flagships of peer-reviewed scientific publications, Science and Nature, are EXTREMELY strict about scientific discoveries to be reported in their pages being embargoed until the date of publication. (That's one reason the Cassini imaging team cites for not sharing many of their most beautiful color images: they don't want Science or Nature to refuse to publish them if they have already been published elsewhere.)
The other answer is that a major scientific meeting is coming up very soon: the annual meeting of the Division of Planetary Sciences of the American Astronomical Society. It's being held in Cambridge, England this year, which is obviously not in America, but DPS has enough international members that they hold the meeting abroad once every few years. And I really, really hope that the team will have something to say there, and that their lips are not still sealed by the Science embargo. In any case, I will be there, jotting down everything I hear, and if I hear anything relevant to the contest, you can be sure I'll let you know!
P.S. A reader has just informed me that if I mentioned Photoshop and ImageJ for image processing, I should also mention GIMP. I've never used it myself but many entries to the Huygens Art Contest were created in GIMP so I know you can do good things with it. If you know of any other excellent freeware resources for image processing, please let me know; I'll compose a list and post it here.