Season 6

E1. Catastrophes that Changed the Planets

Oct 25, 2011 · 45m

The planets of our solar system have experienced epic catastrophes throughout their long history, both raining down from outside and bubbling up from within. We'll voyage back in time to investigate the violent events that profoundly shaped the planets, including earth itself. We'll witness stunning revelations about what transformed Mars into a barren, hostile desert...The disaster that changed Venus from temperate to hellish...The impact that blew away Mercury's mantle, turning it into a planetary core...A colossal disturbance that rearranged the orbits of the gas giants...Titanic impacts on Jupiter...And how a lost moon may finally explain Saturn's rings.

E2. Nemesis: The Sun's Evil Twin

Nov 1, 2011 · 45m

Could there be a monstrous, undiscovered star orbiting our own Sun? Could it be scattering killer comets throughout our Solar System like clockwork every 26 million years? New scientific surveys are probing the edges of our Solar System--a realm populated by giant worlds and mysterious planetoid--hunting for Nemesis, the Sun's purported evil twin. We may be on the verge of discovering this ultimate death star, suspected of causing every mass extinction in Earth's history. We employ everyday experiences to explain what Nemesis is and why it's been so hard to find. Experts start a wildfire on a dry California hillside, race a NASCAR around an oval track, and juggle fire, all in the effort to present how Nemesis works, and why life on Earth may depend on its discovery.

E3. How the Solar System was Made

Nov 8, 2011 · 45m

At 4.6 billion years old, the Solar System is our solid, secure home in the Universe. But how did it come to be? In this episode we trace the system's birth from a thin cloud of dust and gas. Shocked by a nearby supernova, the pull of gravity and natural rotation spun it into a flat disc from which the Sun and planets coalesced. It all happened in the space of 700 million years, during which the planets jockeyed for position, dodging the brutal bombardment of deadly asteroids and setting into the neat, stable system that we now realize might be a rarity in the universe.

E4. Crash Landing on Mars

Nov 22, 2011 · 45m

What might happen if the first manned mission to Mars crashes hundreds of miles from the rocket that would take them back home? Could they survive the crash, and travel across the brutal Martian surface to their home ship? We'll show what the astronauts would have to do to survive dust storms and space radiation, while extracting vital resources like water from the Martian soil itself. It's a dramatic vision of the very near future, where survival can depend on pre-industrial technology and human ingenuity.

E5. Worst Days on Planet Earth

Nov 29, 2011 · 45m

Earth may seem like the most hospitable planet in the solar system. But look again. Startling new discoveries reveal the blue planet has been plagued by more chaos and destruction than scientists once imagined. Stand on the Earth billions of years ago as a primitive planet slams into it. Shiver as our entire globe is frozen over like a gigantic snowball. Feel the heat as mammoth volcanoes scorch the landscape and darken the sky. From a cosmic gamma ray burst frying away the ozone layer to an Everest-size asteroid slamming into the ocean, we'll reveal new information about how these unparalleled events drove life to the brink of total extinction. Out of this continuous devastation, how has our planet--and life--got to where it is today? Are the worst days behind us--or lurking in the distant future?

E6. How Big, How Far, How Fast

Apr 29, 2012 · 45m

The biggest objects, farthest distances, and fastest speeds are made relatable through extreme physical analogies.

E7. UFO: The Real Deal

Dec 13, 2011 · 45m

Many argue that flying saucers and other extra-terrestrial space ships continuously visit the earth. If that were true, what kinds of technologies would such alien spacecraft require? And do eyewitness reports of UFO sightings jibe with modern theories of how interstellar travel might be possible? Authors, astronomers and theoretical physicists weigh in with the blueprints for inertia-canceling devices, nuclear-powered craft, antimatter propulsion systems and even warp drives. Based on Einstein's theories and countless scientific studies, we'll find out how these visitors might bridge the vast distances between the stars. And if they could survive such hazardous journeys, are they flesh and blood or intelligent machines?

E8. God and the Universe

Dec 20, 2011 · 45m

Since the dawn of civilization, humans have wondered who or what created the universe. Religion offers a spiritual answer, but do the latest discoveries in physics show evidence of a transcendent intelligence, or simply that the laws of physics by themselves could have led to the universe in which we live? This episode embarks on a mind-bending scientific search for God, asking physicists and theologians if the seemingly miraculous way the universe has been calibrated to support life is evidence of a creator...whether string theory will eventually be able to rule out the existence of God...why Stephen Hawking says the universe could have been created spontaneously...and how an advanced civilization in another universe could have conceivably created our own.

E9. Alien Sounds

May 6, 2012 · 45m

What does the Universe sound like? From the sweep of a pulsar, to the deafening roar of our boiling sun this episode explores the undiscovered soundscapes of the solar system, the galaxy, and the entire cosmos. And, is it true that in space nobody can hear you scream?!? Our scientists reveal that there are places in the Universe that prove this sci-fi statement wrong.

E10. Our Place in the Milky Way

May 13, 2012 · 45m

An exploration of Earth's cosmic neighborhood. Looking beyond the borders of our solar system, what's nearby in our galaxy? How do the other objects in our local area influence life on Earth? And, how did Earth's place in the galaxy make it the perfect place for the development of advanced life?

E11. Deep Freeze

May 20, 2012 · 45m

This episode discusses the coldest places in the universe from labs on earth to super cold places in our solar system, galaxy and beyond.

E12. Microscopic Universe

Jun 3, 2012 · 45m

An examination is conducted into the world of miniature particles, as microscopic objects like neutrinos MACHOs, WIMPs and many others may ultimately lead to understanding more about the mysteries surrounding the cosmos.

E13. Ride the Comet

Jun 10, 2012 · 45m

A comet travels to the sun from the outer reaches of the solar system.

E14. When Space Changed History

Jun 17, 2012 · 45m

Objects from space have changed history throughout the ages.