It was not one thing Frank Drake got down to do, but it surely appeared fairly helpful. In 1961 he was drawing up an inventory of subjects for a convention he had convened on the Nationwide Radio Astronomy Observatory at Inexperienced Financial institution, West Virginia. This could collect in each scientist on the earth who cared about clever life elsewhere within the universe; about 12 individuals, by his reckoning. One among them was researching what dolphins stated to one another. His personal query went considerably additional: whether or not there have been civilisations past our photo voltaic system, and what they is likely to be attempting to say.
He had finished his first seek for extraterrestrial intelligence (later referred to as seti) the yr earlier than. That enterprise was nonetheless extensively ridiculed as a hunt for little inexperienced males, Martian canal-builders and ufos, and never respected analysis. (Maybe unwisely, he referred to as it Challenge Ozma, after the daughter of the King of Oz.) So he saved it secret, and the convention casual, to keep away from public mockery. However seti for him was an expression of significant scientific intent.
He was excellently positioned to embark on it. As a radio astronomer, he spent his days controlling the 26-metre telescope at Inexperienced Financial institution, observing and recording in pen and ink (no computer systems then) the information that reached Earth from the radio a part of the electromagnetic spectrum. That finer, sharper instrument allowed him to seek out the radiation belts of Jupiter, to analyse the environment of Venus and to map the centre of the Milky Means, obscured to seen gentle by clouds of mud. Occasionally he additionally pointed the telescope at two stars, Tau Ceti and Epsilon Eridani, which he thought probably to be liveable and sending radio indicators.
He felt no must justify that fascination. Ever since Sunday college, to which he was despatched by his strict Baptist mother and father, he had been struck by how naturally individuals assumed that their very own civilisation was the one one price understanding. He resolved then, at eight, to not suppose that manner. On the Chicago Museum of Science and Business, a favorite hang-out, he discovered that the Solar was merely a mean star amongst billions. He felt then, and each time he gazed at a transparent evening sky, that clever life couldn’t be a fluke that had appeared solely on Earth. Because it had occurred in any respect, why not elsewhere?
It will do no hurt, he thought, to provide his researches the dignity of an equation, and that day in 1961 one got here fairly naturally:
N= R* x fp x ne x fl x fi x fc x L
As he opened the assembly, he wrote it on the blackboard. N was the variety of detectable, clever civilisations within the Milky Means galaxy; to get that determine, you simply multiplied the components collectively. R* was the common charge of formation of stars in our galaxy: between one and ten a yr, he thought. After that, fp was the fraction of stars that had planets, and most stars had them. Subsequent, ne was the common variety of these planets that would probably assist life (Earth, Mars and Venus in his estimation); fl the fraction of these on which life had really developed; fi the fraction of these on which that life was clever; and fc the fraction of people who had produced a expertise detectable from area, just like the radio-wave transmitters he was utilizing himself.
This was probably not an equation, however a considering instrument. Folks referred to as it pure hypothesis, however every phenomenon had taken place within the universe not less than as soon as. It grew to become so well-known that it featured on t-shirts, proper subsequent to Einstein’s e=mc2. In fact, a lot of the phrases had no recognized values. However the really troublesome one was the final, L, which was the common size of time a civilisation is likely to be detectable. That was fairly not possible to say. The determine he often threw out was 10,000 years.
Regardless of the imponderables, he and his colleagues began looking. On the very first day of the experiment an everyday pulse, eight occasions a second, was detected from Epsilon Eridani—but it surely turned out to be rogue radar from a passing plane. Greater than 100 different initially intriguing indicators had been seen, however all had been most likely artefacts. NASA had arrange some funds for SETI from the Nineteen Seventies, however no correct programme till the Nineteen Nineties, by which era Congress was shedding persistence. In 1993 it turned off the faucet. When Dr Drake was requested why nothing had been discovered, he replied: “We haven’t tried laborious sufficient.” They’d noticed only some thousand stars, when they need to have noticed 10m, and so they wanted two antennae on reverse sides of the Earth to look in all instructions on a regular basis. It might be finished, however solely with a pile of cash.
If faraway intelligences didn’t get in contact, they could maybe be nudged to reply to messages. In 1974 he despatched the primary interstellar message from the Arecibo Observatory in Puerto Rico in direction of m13, a globular star cluster 25,000 light-years away. In easy binary coding, it described the place the message was from and what people had been like. He additionally collaborated with Carl Sagan, then America’s best-known astronomer, to connect plaques to the Pioneer spacecraft and pictures and audio recordings to the Voyager craft, describing Earth and earthlings. Pictures of Earth-life despatched on Voyager included certainly one of him, or somebody very like him, consuming a sandwich in a manic trend. He was by no means that eager, nevertheless, on sending issues. Earth had been lit up like a beacon with radio transmitters for many years. If different civilisations wished to make contact, they knew the place to direct their indicators.
Different scientists might need been depressed by the shortage of progress. It didn’t pace up even when new telescopes may produce reams of information in seconds, fairly than months. However he was not forged down. His work had develop into a part of a wholly new subject of interdisciplinary analysis, astrobiology. Moreover, his star-gazing on Tau Ceti and Epsilon Eridani was like shopping for two tickets for the lottery. To find clever life past the photo voltaic system would alter humankind’s notion of itself profoundly, and never solely by curbing its conceitedness. It will probably train earthlings new applied sciences, new methods of seeing and—he particularly appreciated this thought—new sources of pleasure. It will be the most important jackpot possible. And somebody, someplace, needed to win it. ■
This text appeared within the Obituary part of the print version below the headline “The “Are we alone?” equation”