Cradle of Life As We Know It
Earth is the only place we know of in the universe that harbors life. Ours is the largest terrestrial planet in the solar system. Our rocky, volcanic world is coated in a thin veneer of liquid water, living things, and translucent atmosphere, whose complicated interactions make Earth's surface into a place of constant change. We humans have only had fifty years of perspective on Earth as a planet, of seeing it as a "pale blue dot" floating in the black vacuum of space.
With that perspective, we know precious and unique our planet is. We know, too, that we are having measurable effects on the complex interactions of ocean, land, life, water, and air, changing our climate. But predicting the future of our climate is hard. Understanding how Earth's systems work by studying the way they operate on other worlds is a major goal of planetary exploration. Mars, Venus, and Titan all have (or had) active geology, hydrology, and weather -- but, as far as we know, they don't have life. Is Earth really that unique? Are we truly alone in the universe? We won't know unless we keep searching.
News from Earth
On December 1 at 17:30 UTC, Chang'e 3 launched atop a Long March 3B rocket on a direct lunar transfer trajectory. It is scheduled to enter orbit December 6 and land December 14. The rocket was equipped with cameras that recorded thrilling video of the launch and final departure of the probe.
Earth's Place in Space
Our Curiosity Knows No Bounds!
Become a member of The Planetary Society and together we will create the future of space exploration.