Deep Impact is the NASA project to smack a probe into the surface of a comet in order to get some insights into what it's made of. The impact event will happen on Monday, July 4. The comet -- which will by no means be destroyed -- is Comet Tempel 1. The impact will be watched by a variety of space probes, and will be visible from some parts of the Earth.
Why do this? Two main reasons. The first is that comets have, by and large, been around since the formation of the solar system, and taking a look at the guts of one can give some added clues about how the planets came to be. The second will be familiar to regular readers of WorldChanging: it will help us better understand how to keep comets from hitting the Earth. They don't hit very often, but when they do...
A final digression: if scientists are concerned about Hollywood mangling science in the service of entertainment, they probably shouldn't be using Hollywood names for their projects to get more attention. Just saying.









