In this excerpt from Five Billion Years of Solitude author Lee Billings chronicles the pioneering scientists who have led the hunt for extraterrestrial intelligence in their quest to answer the haunting question: Is humanity alone in the universe?

Reprinted from Five Billion Years of Solitude: The Search for Life among the Stars, by Lee Billings. With permission of Current, a member of Penguin Group (USA), LLC, A Penguin Random House Company. Copyright © Lee Billings, 2013.

On a hillside near Santa Cruz, California, a split-level ranch house sat in a stand of coast redwoods, the same color as the trees. Three small climate-controlled greenhouses nestled alongside the house next to a diminutive citrus grove, and a satellite dish was turned to the heavens from the manicured back lawn. Sunlight filtered into the living room through a cobalt stained-glass window, splashing oceanic shades across an old man perched on a plush couch. Frank Drake looked blue. He leaned back, adjusted his large bifocal glasses, folded his hands over his belly, and assessed the fallen fortunes of his chosen scientific field: SETI, the search for extraterrestrial intelligence.

“Things have slowed down, and we’re in bad shape in several ways,” Drake rumbled. “The money simply isn’t there these days. And we’re all getting old. A lot of young people come up and say they want to be a part of this, but then they discover there are no jobs. No company is hiring anyone to search for messages from aliens. Most people don’t seem to think there’s much benefit to it. The lack of interest is, I think, because most people don’t realize what even a simple detection would really mean. How much would it be worth to find out we’re not alone?” He shook his head, incredulous, and sunk deeper in the couch. Besides a few extra wrinkles and pounds, at eighty-one years old Drake was scarcely distinguishable from the young man who more than half a century earlier conducted the first modern SETI search. In 1959, Drake was an astronomer at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. He was only twenty-nine then, lean and hungry, yet he already possessed the calm self-assurance and silver hair of an elder statesman. At work one day, Drake began to wonder just what the site’s newly built 85‑foot- wide radio dish was capable of. He performed some back‑of‑the- envelope calculations based on the dish’s sensitivity and transmitting power, then probably double-checked them with a growing sense of glee. Drake’s figuring showed that if a twin of the 85‑footer existed on a planet orbiting a star only a dozen light-years away, it could transmit a signal that the dish in Green Bank could readily receive. All that was needed to shatter Earth’s cosmic loneliness was for the receiving radio telescope to be pointed at the right part of the sky, at the right time, listening at the right radio frequency.

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