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
It's taken me a year to face the emotionally draining task of reading and writing about Galileo's cruise phase as chronicled in the mission's newsletters.
I am happy to announce a new call for proposals for The Planetary Society’s Gene Shoemaker Near Earth Object (NEO) grant program, which is celebrating its 15th Anniversary. Proposals are due Feb. 4, 2013.
Posted by Björn Jónsson on 2012/11/13 05:24 CST
This is a very large (19000 pixels square) mosaic of the fjords and glaciers of southern Greenland. I had been interested for a long time in experimenting with the processing of Earth satellite imagery just to get a comparison to the other planets.