Concern about asteroids, meteors, and other near-earth objects has increased in the past few years due to events like the Chelyabinsk meteor crash. Like meteors, asteroids have interacted with Earth in the past, and will continue to do so in the future. In this podcast, join Amy Mainzer as she explains what an asteroid is, their origins in the solar system, and systems in place on Earth to discover, track, and predict impacts from Earth's nearest neighbors. This lecture took place at the Hayden Planetarium on February 3, 2014.