If we could find them, we could end our history-long loneliness, and we could imagine—through the example of their very existence—that we, too, could make it to some kind of higher, more heavenly reality.
That is not quite how scientists tend to frame their work. And they do not tend to say that it requires faith, either. An outside observer might think that SETI scientists believe in ET—otherwise, why would they spend years searching? But most actually reserve judgment, and maintain at least outward agnosticism. What keeps most motivated is not belief, or dogmatic pursuit of a foregone conclusion, but the importance of the potential discovery: There’s a low probability any given scientist in any given era will succeed in finding alien life, but—if they do—the consequences are significant. You know, like transforming our conception of life, the universe, and everything.
Despite the magnitude of that potential finding, federal science has mostly left SETI out of its spreadsheets for decades. But in a 2018 reversal, NASA hosted a workshop to determine how best to search for alien technology. And outside of that support, scientists have also started a slew of new projects, and begun training more fledgling researchers. The alien hunt, in other words, is having a bit of a moment.
The History of the Hunt for Aliens
It all began in the middle of nowhere: Green Bank, West Virginia. The site’s remoteness is precisely why, in the 1950s, astronomers decided to build radio telescopes way out here, far from the contaminating influence of human technology. One of Green Bank’s early employees was a man named Frank Drake. Drake, like many scientists, read a 1959 Nature paper by physicists Guiseppe Cocconi and Philip Morrison, who suggested that if a person wanted to find intelligent aliens (here, “intelligent” means capable of using technology to transmit an identifiable signal) they might try picking up radio broadcasts, and they suggested a range of frequencies scientists could search. This fired Drake up, and in 1960 the observatory’s director agreed to let him point an 85-foot telescope at two sun-esque stars, tuning it in to the kinds of transmissions that could come from technology and not from stars, gas, or galaxies.
It didn’t, but the effort, called Project Ozma, kicked off the modern SETI enterprise. A year later, Green Bank hosted a secret National Academy of Sciences meeting at which Drake presented the now-famous and now-eponymous Drake Equation. It posits that if you know how often stars are born in the galaxy, what percentage have planets, what number of those planets are habitable, what fraction of habitable planets are inhabited, what fraction of inhabitants are intelligent, what fraction develop interstellar communication, and how long technologically intelligent civilizations survive, you could figure out how many extraterrestrial societies await your discovery. It was never meant to be be precise math: It was just a meeting agenda.
Around a decade later, NASA convened a study called “Project Cyclops.” In it, scientists laid out what alien contact might look like and how, engineering-wise, they might accomplish it. They devised a hypothetical radio telescope made of many antennas that work together as one. While at full scale, it would be cost between $36 billion and $60 billion in 2018 dollars, the attendees suggested it be made in modular fashion—a few antennas here, check for aliens. No aliens? Add a few more, look some more. Still nothing? Break ground again. Etc.
The project never happened, but it did inspire Berkeley professor Stuart Bowyer and Berkeley student Jill Tarter to start a smaller-scale program called SERENDIP: the Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations. Berkeley now has a SETI Research Center, and SERENDIP still exists—in its sixth iteration, using both the Green Bank Telescope and the Arecibo telescope in Puerto Rico. Since the turn of the century, the program has also let you help process data through the SETI@Home program, which uses your idle CPU to hunt for potential communications.
In the 70s, Ohio State started a SETI project at its Big Ear Observatory, and caught the famous WOW! Signal—a mysterious burst of radio waves that has captured attention for decades but, sorry, is not aliens. For a while, NASA had a nascent SETI program, and when it officially began operations in 1992, astronomers had good reason to hope for a “hello” from light-years away: Around this time, scientists discovered the first-ever planet beyond our solar system, around a pulsar, and would soon find another one, this time orbiting a star like the Sun. All those aliens, turns out, might have at least a few places to live. Plus, back on Earth, scientists were learning more about the badass microbes that live in hot, cold, acidic, basic, salty, radioactive, and just generally unpleasant spots. If life could find a way in all that mess, why not around Zeta Reticuli?