In 1964, a pair of radio astronomers, American physicist Robert Wilson (1936-) and German-born physicist Arno Penzias, working for the Bell Telephone Laboratories in Holmdel, New Jersey, stumbled upon the best evidence in existence to support the big bang model of cosmogenesis. Penzias and Wilson were recalibrating a radio antenna originally built to bounce signals off of Echo, the first telecommunications satellite. The same antenna was to both transmit and receive microwave signals from the second such satellite, Telstar. The astronomers-turned-radio engineers were measuring the antenna's gain (its power to amplify faint signals), and were looking out of the plane of the Milky Way. No matter where the antenna was pointed, whether at a radio source or at empty space, they detected a very faint, very uniform signal. The intensity of the radiation they found was identical to that emitted by a body at a...