Do you believe in miracles?

[Thorne]

The fact that the universe exists at all, and is capable of supporting any life form is a miracle. Repeated many times over on just one planet.

And maybe not just one. Scientists are finding increasing evidence of the possibility of life on other planets. They apparently found meteorites in Antarctica which have been shown to have come from Mars, and which seemed to contain bacterial fossils. I believe they've also seen video evidence from one or both rovers on Mars of erosion patterns which are consistent with biological wearing, such as from lichen growing on rocks.

The probability that Earth is the only habitat of life in the universe is so negligibly small as to be virtually impossible. Given the millions of stars in our galaxy and the thousands upon thousands of galaxies which we can see, it is almost a foregone conclusion that life of some sort exists elsewhere. And the lessons we are learning even here on Earth about extremophiles makes it that much more likely that life, and perhaps intelligent life as well, can occur almost anywhere. No miracles required.