Right now, massive meteors and asteroids are orbiting dangerously close to Earth. Some may even be poised to hit us in the foreseeable future! Where are they? What type of damage will they cause? What can we do stop a caroming asteroid thats headed toward us, or prevent future Near Earth Objects from lining us up in their sites.Episodes:EARTH: They have left deep scars all over the face of our planet and are responsible for one of the biggest extinctions in history. Scientists believe that its not a question of if theyll strike again, but when.Cosmic Collisions: Earth covers everything there is to know about meteor clashes with our planet and how scientists are preparing for the next deadly assault on Earth.SOLAR SYSTEM: Our solar system is a cosmic pinball machine. Rock piles as big as cities plow into planets and leave destruction in their wake. Cosmic Collisions: Solar System travels through our cosmic neighborhood as we examine how collisions created our moon, left gashes on Jupiter, and how pieces of Mars ended up in our own backyard.GALAXIES: Galaxies smash into each other, stars collide with the force of several nuclear bombs and black holes fuse in a deadly fireworks display.  Even our own galaxy marches toward a clash with its closest neighbor, Andromeda. Cosmic Galaxies journeys through space as we examine the cosmic battles being waged between celestial bodies.PREHISTORIC DISASTERS: Since the Earth's creation 4.5 billion years ago, the planet has been struck by a series of catastrophes, each one pushing life to the edge of extinction. But from disaster comes new life - and while the dominant species on the planet were wiped out, hardier creatures survived and thrived, moving into the vacuum left by the extinction. These creatures in turn took over the planet until they themselves fell victim to yet another mass extinction.  The Earth's history is rife with prehistoric disasters that have molded the planet and changed the course of evolution.  But with each disaster came another leap forward on the evolutionary trail from single celled bacteria to humankind itself. Without this series of events, neither mankind nor any of the life we see around us would be here today. Episodes: Birth of the Planet, Snowball Earth, Planet of Fire, Asteroid Strike.