Earth Atmosphere

Why Earth Is Unique -- So Far (Fox News)

8 Jul 2008

Some astrophysicists worry we'll never find another planet that has Earth's half-dozen life-sustaining characteristics.

What makes Earth so special? (MSNBC)

8 Jul 2008

Understanding what's special about Earth is crucial for finding other planets out there and predicting what they might be like.

What Makes Earth Special Compared to Other Planets (SPACE.com)

8 Jul 2008

Earth has liquid water and plate tectonics, but its most special feature might just be us.