habitable

“Next to reasoning, the greatest handicap to the optimum development of Man lies in the fact that this planet is just barely habitable. Its minimum temperatures are too low, and its maximum temperatures too high. Its day is not long enough, and its night is too long... These factors encourage depression, fear, war, and lack of vitality. They describe a planet, which is by no means perfectly devised for the nurturing or for the perpetuation of a higher intelligence.” -James Thurber It's been just about three years, now, since the first announced discovery of a planet in another star system…

"Death comes to all, but great achievements build a monument which shall endure until the sun grows cold." -Ralph Waldo Emerson In the great cosmic ocean, there's only one planet that we know -- for certain -- has the right conditions and history to result in intelligent life: our own. Image credit: NASA, from the Space Shuttle, for Sun-Earth Day 2008. Life -- or even intelligent life -- may be possible in environments vastly different than our own: around different classes of stars, at different temperatures, and even with different molecules and/or chemical elements. But we know for…