Astronomers now know that the galaxy is teeming with at least as many planets ”” the presumed sites of life ”” as stars. Advanced life and technology might be rare in the cosmos, said Geoffrey W. Marcy, the Watson and Marilyn Alberts in the Search for Extraterrestrial Intelligence professor at the University of California, Berkeley, “but surely they are out there, because the number of Earthlike planets in the Milky Way galaxy is simply too great.”
A simple “howdy,” a squeal or squawk, or an incomprehensible stream of numbers captured by one of the antennas here at the University of California’s Hat Creek Radio Observatory would be enough to end our cosmic loneliness and change history, not to mention science. It would answer one of the most profound questions humans ask: Are we alone in the universe?
Despite decades of space probes and billions of NASA dollars looking for life out there, there is still only one example of life in the universe: the DNA-based web of biology on Earth. “In this field,” said Jill Tarter, an astronomer at the SETI Institute in Mountain View, Calif., the “number two is the all-important number. We count one, two, infinity. We’re all looking for number two.”