Duane Swierczynski

August 1977. Astronomers detect the so-called "WOW" signal: a burst of sound from deep space, near the constellation Sagittarius. The signal is believed to be extraterrestrial in origin. The next month, the astronomers send a reply. Boy, is that a huge mistake. Because more than four decades later, the alien intelligence has sent an invasion force of exactly one photon―and it's the kind of microscopic threat we could have never seen coming… In...