You all know I love space exploration. I am excited by the discovery of Kepler-22, the first potentially human habitable planet discovered by NASA’s Kepler spacecraft. But here’s what gets me. Notice how I said “human habitable”. Everyone else just say “habitable”. There is the assumption that life couldn’t have formed on a planet that humans couldn’t live on. Hydrogen based life, perhaps, couldn’t form on a planet without water as we know it, but why are we so certain that all intelligent life has to be hydrogen based? And why are we certain the planets need to be Earth-size?