Mysteries of Meteors, Asteroids and Comets (Solving Space's Mysteries)

What are asteroids, comets and meteors made of? What can scientists do if an asteroid is heading towards Earth? Learn how astronomers prepare for space objects hitting Earth, from tracking them to building asteroid-hunting telescopes. Budding astronomers will learn all about meteors, asteroids and comets, including the history of asteroids hitting Earth and the differences between space rocks.