Deep Impact

I spent a little time watching the live coverage of the Deep Impact missions rendevouz with the comet Tempel 1. What a fabulous piece of engineering. Initial reports told of a flwless execution of something which has never been done before. The folks over at JPL were rather impressed by the large amount of ejecta produce by the collision. I have my theories about what may be going on there. This is likely to become a little technical so bear with me.

Scientists have long described comets as muddy ice balls. I believe that as the more volitile ice submlimates away into space with each pass the comet makes close to the sun, the mud in that muddy ice ball mix remains as a layer on the comet's surface. As time passes, this mud layer would grow thicker, creating a protective insulating blanket over the surface. This blanket would then shield the volitile ices that still exist within the comet's core, slowing its sublimation into space.

The large amount of ejecta that they've witnessed would then be because the impactor excavated a hole through this protective layer of mud, allowing a larger amount of ice to be exposed and sublimated off into space. This sublimation is further increased as the impactor would have been super heated by the friction of the impact itself, causing a larger amount of ice to sublimate than could have been normally accounted for by solar heating.

Time will tell if my theory is correct, once NASA has had a chance to review the data. It should be fun to see if my hunch is correct.