Glacier Meltdown

S04 E01 • Wednesday, Jan 31, 2007 • Jan 31

Destructive Forces

S04 E02 • Wednesday, Feb 21, 2007 • Feb 21

Stone Age Apocalypse

S04 E03 • Wednesday, Feb 28, 2007 • Feb 28

Comets

S04 E04 • Wednesday, Mar 7, 2007 • Mar 7

Prehistoric Americans

S04 E05 • Wednesday, Mar 14, 2007 • Mar 14

Deep Space Probes

S04 E06 • Tuesday, Mar 27, 2007 • Mar 27

Great distances and dangerous environments make robotic spacecraft the best way for scientists to explore our solar system. Acting as our eyes and ears, these probes have revealed secrets about the distant planets and their moons, their surfaces, weather and environments.

Dino Meteor

S04 E07 • Thursday, Apr 12, 2007 • Apr 12

Planet Storm

S04 E08 • Thursday, Apr 26, 2007 • Apr 26

Polar Apocalypse

S04 E09 • Sunday, Apr 1, 2007 • Apr 1

Killer Lakes

S04 E10 • Thursday, May 3, 2007 • May 3

Since the death of 1,700 people near a lake in Africa, scientists have uncovered a terrifying series of hazards in lakes across the world.

Ring of Fire

S04 E11 • Thursday, Aug 2, 2007 • Aug 2

Alien Safari

S04 E12 • Thursday, Aug 9, 2007 • Aug 9

With advanced technology in their hands, astronomers and scientists may now be capable of detecting extraterrestrial life in the universe. In fact, some think the proof may be found in as little as a decade. Astronomers involved in the effort, including those at SETI (Search for Extraterrestrial Intelligence), discuss the possibilities and the likely spots for finding life outside of Earth.

Hyper Hurricanes

S04 E13 • Thursday, Oct 18, 2007 • Oct 18

Dangers of the Deep

S04 E14 • Thursday, Oct 25, 2007 • Oct 25

Solar Force

S04 E15 • Tuesday, Oct 30, 2007 • Oct 30

Birth of the Solar System

S04 E16 • Tuesday, Nov 6, 2007 • Nov 6

Thanks to new developments in the technology of astronomy, scientists have been able to collect new information, giving them clues to how our solar system was formed.

Hubble Trouble

S04 E17 • Tuesday, Nov 6, 2007 • Nov 6