Join or Sign In
Sign in to customize your TV listings
By joining TV Guide, you agree to our Terms of Use and acknowledge the data practices in our Privacy Policy.
4 Episodes 2008 - 2008
Episode 1
Tue, Apr 1, 2008 60 mins
A look at Earth's unique and complex atmosphere reveals its origins and the role it plays in our survival.
Episode 2
Tue, Apr 8, 2008 60 mins
Probing the controversial "snowball Earth" theory, which suggests that the entire planet was once entombed in ice for millions of years.
Episode 3
Tue, May 20, 2008 60 mins
The unique landscapes and animals living in Alaska's Denali National Park and Preserve are spotlighted.
Episode 4
Thu, May 22, 2008 60 mins
Scientists discuss the devastating cyclone that struck Myanmar on May 2, 2008, and left an estimated death toll of 100,000 in its wake. Included: footage of Myanmar's ravaged countryside.