As we discover more and more planets around other stars, the Fermi Paradox is becoming, well, more paradoxical.
The Fermi Paradox simply asks the question "where are they?" Our Milky Way galaxy is so big and so old - and we are estimated to be accompanied by at least 100 billion planets - that aliens should have visited us by now.
Instead, when we peruse the heavens, we are faced with the Great Silence, which is one of the biggest challenges to modern astronomy.
There have been numerous solutions to the Fermi paradox, but none of them are satisfactory.
A few diehards like Harvard astronomer Howard Smith are emphatic that we are completely alone in the universe. As much as I disagree, there isn't a shred of evidence to the contrary. Nevertheless, I do wholeheartedly agree with my colleague Seth Shostack of the SETI Institute who says that it would be a miracle if we didn't find advanced life out there.
Picking up on this idea, Canadian science fiction writer Karl Schroeder has come upon a novel solution to the failure of astronomical observations to solve the Fermi Paradox. He proposes: "any sufficiently advanced technology is indistinguishable from nature." (This is a takeoff on Arthur C. Clarke's posit: "any sufficiently advanced technology is indistinguishable from magic.")