In the pristine wilderness of Northern California 42 dishes in the Allen Telescope Array–a group of centimeter-wave radio telescopes–constantly scan the heavens. Built on the Large Number, Small Diameter theory of radio telescopes, the ATA is constantly listening to the stars for the faintest sign that extraterrestrial life is sending out signals.

The ATA is [...]

Gene Cernan was the last human to step off the Moon when Apollo 17 set off on their return trip to Earth in December of 1972.  From the time Neil Armstrong made the first famous step on the lunar surface on July 20, 1969, until December 14, 1972, when Mr. Cernan, Jack Schmitt, and [...]