The greatest revelation of planetary exploration has not been how different are other worlds, but how much like Earth they are. Photographs from the surfaces of the Moon, Mars, Venus, and now Titan might have been taken in a terrestrial desert or Antarctic waste.
Just 400 years ago people believed that everything that existed above the sphere of the Moon belonged to another changeless world, utterly different than Earth. We now know that the laws of energy and matter that shape our planet are universal, and among the billions of galaxies we can see with our telescopes we should not be surprised to find countless other Earthlike worlds and intelligences both greater and lesser than our own.
This new information does not sit well with certain religious beliefs that evolved at a time when we believed ourselves to be the sole proprietors of the creation. But as the biologist E. O. Wilson has said, "If history and science have taught us anything, it is that passion and desire are not the same as truth."