The field of planetary science is currently enjoying an intense period of readjustment and discovery.

The mission is to understand what a comet is made of and how it's put together.

Ten years ago, we would have been blissfully ignorant.

Comets are thought to be icy dirtballs made up of exotic ices, dust, and rock particles,

The beauty of comets is that they are important to us. We probably would not be here were it not for comets. Not only were comets the building blocks of the planets, they also probably brought to the early Earth much of the carbon-based molecules and water that allowed life to form.

There's a few nervous people, to be sure. There's a lot of things that could go wrong.