David Waltham on Earth as the Oddball PlanetLucky Planet: Why Earth is Exceptional — and What That Means for Life in the Universe (Basic Books: 2014), pp. 1-2.
The proposition that Earth may be an oddball, a planet quite unlike any other we will ever find, has been discussed for centuries. Until recently such debates were built on mere speculation, but times are changing. We now sit at one of those scientific crossroads where a field of study moves from being a disreputable, if interesting, subject for discussion to a real science with defendable conclusions based on substantial evidence. Such transitions occur when technological advances make previously impossible observations routine and, as a result, new data becomes available. ¶ In the case of oddball Earth, the new data comes from advances in how we look at the rocks beneath our feet and at the stars above our heads. The rocks tell a tale of our planet’s constantly changing environment along with the history of life-forms and their struggles to survive. The stars speak of many possible worlds, all unique in their own way. These parallel stories suggest that incredible good fortune was needed to allow human existence. … Personally, I no longer have doubts. The evidence points toward Earth being a very peculiar place; perhaps the only highly habitable planet we will ever find. This view has led some astrobiologists to describe me as “gloomy,” but I don’t see things that way. For me, these ideas merely emphasize how wonderful our home is and how lucky we are to exist at all.