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
Our preview of spaceflight in 2017 starts with highlights of missions and events happening on and around our home planet.
Today is the solstice, the longest winter night at Earth's north pole, the longest day of summer in the south. To give a little light to northerners in darkness today, please enjoy this gallery of images of (mostly) sunlit north poles across our solar system.
Earth's Place in Space
An asteroid or comet headed for Earth is the only large-scale natural disaster we can prevent. Working together to fund our Shoemaker NEO Grants for astronomers, we can help save the world.