We live on a planet that was born from cosmic bombardment and we continue to take hits daily. Most are small, some are as large a the one that ended the dinosaurs. Thats why we are sending space probes to explore these potential threats to Earth. Scientist from all over the globe want to learn what these small bodies are made of, where they where from and why they behave the way they do. Because while they may have seeded the building blocks of life on Earth they could just as surely take it away.