“How many kingdoms know us not!”—Blaise Pascal, Thoughts (1670) One summer’s day in 1950, the great Italian-American physicist Enrico Fermi was having lunch with the physicists…

After midnight in a sweltering room in Pasadena in July 1976, Viking Mars team members sat hunched around a bulky monotone computer monitor, tensely awaiting the first data from the…

Valencia, Spain, Oct. 6, 2006. After four long days, the 57th International Astronautical Congress draws to a close, and two prominent members of the Search for Extraterrestrial Intelligence…

Last January I was walking with my granddaughter along a beach near Melbourne when we noticed several people gathered around a rock pool, peering into the water. Wondering what had…

If one is looking for signals from an extraterrestrial civilization, why not practice on some of the non-human communication systems already known on our own planet? Whales have had…

On the day that I was born—winter solstice, 1959—a headline in Life magazine proclaimed “Target Venus: There May be Life There!” It told of how scientists rode a balloon to…

Perhaps Arthur C. Clarke was being uncharacteristically unambitious. He once pointed out that any sufficiently advanced technology is going to be indistinguishable from magic. If you…

This September, a team of astronomers noticed that the light from a distant star is flickering in a highly irregular pattern.1 They considered the possibility that comets, debris,…

A rocket powered by kerosene and liquid oxygen and carrying a scientific observatory blasted off into space at 10:49 p.m., March 6, 2009 (by local calendars and clocks). The launch…

At a distance of 3.7 billion miles from the sun, on an otherwise ordinary February day in 1990, the Voyager 1 probe turned to point its camera platform away from its headlong rush…