with Dr, Michael Busch (SETI Institute) Near-Earth asteroids are a population of small bodies whose orbits around the Sun cross or come near our planet’s orbit.  They turn out to be unusual physical environments: essentially rubble piles. They represent a natural hazard we ignore at our peril, because some of these bodies have the potential to impact Earth.  Dr. Busch reviews the near-Earth asteroid population, programs to track and characterize such asteroids, and current efforts to address the danger of asteroid impacts.