The serious hunt for alien life

Bring up aliens and a lot of people will scoff. But not everyone is laughing. Around the turn of the century, 3.8 million people banded together in a real-time search for aliens — with screensavers. It was a big moment in a century-long concerted search for extraterrestrial intelligence. So far, alien life hasn't been found. But for scientists like astronomer James Davenport https://astro.washington.edu/people/james-davenport, that doesn't mean the hunt is worthless. It doesn't mean we should give up. No, according to Davenport, the search is only getting more exciting as new technology opens up a whole new landscape of possibilities. So, today, we're revisiting our episode on the evolving hunt for alien life. Want more space content? Let your opinion be heard by dropping us a line at [email protected] mailto:[email protected]! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave http://plus.npr.org/shortwave. See pcm.adswizz.com https://pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. NPR Privacy Policy https://www.npr.org/about-npr/179878450/privacy-policy

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• 0:00Speaker 00

  This message comes from Planet Visionaries. Host Alex Honnold sits down this season with extraordinary doers, creating real climate solutions. Listen or watch wherever you get your podcasts.

• 0:12Regina Barber?

  You're listening to Short Wave from NPR.

• 0:17Regina Barber?

  When I was a teenager in the late 90s, I downloaded a special screensaver. It had lots of pretty colors and graphs, but that's not why I wanted it. My goal was to humbly contribute to humankind's search for intelligent life in the universe, aka aliens. This effort is officially called the Search for Extraterrestrial Intelligence, or SETI. The screensaver I downloaded, called SETI at Home, was part of a large-scale community project to use people's everyday PCs to comb through radio signals that hit Earth from space, mostly from stars.

• 0:54Regina Barber?

  These signals have particular patterns. So if astronomers find a signal that doesn't quite fit those patterns, it could mean some intelligent life is sending them. Within a few years, the SETI-at-Home project recruited 3.8 million people.

• 1:08Speaker 02

  I hijacked my parents' little Gateway 2000, and I absolutely cooked it, trying to contribute to what seemed like the thing, right? It seemed like the one opportunity, living in the middle of nowhere in sort of rural eastern Washington, like, oh, I can be part of this journey that humankind is on. It was amazing.

• 1:25Regina Barber?

  That's my friend James Davenport. He's an astronomer at the University of Washington, and his focus is on stars. And I talked to him recently because, importantly for this episode, he's a collaborator with the SETI Institute, a nonprofit research organization that combs through astronomical data in search of signs of life outside of Earth. It's a search that goes way back, way before James and I took control of our family's computers, in 1924.

• 1:50Regina Barber?

  When many researchers were excited about Mars, and Mars' orbit was close to Earth, making it a prime time to listen to signals from the planet. And so, an unconventional astronomer named David Todd convinced multiple radio stations in the US and one in South America to go silent.

• 2:07Speaker 02

  So for five minutes on the hour for several days, they would blackout all radio transmissions in the US. And they would listen. They would point the radio telescopes or the radio transmitters they had at Mars, and they would listen for signs of Martian NPR.

• 2:23Regina Barber?

  David Todd even convinced the US Army and Navy to listen for anything unusual in radio signals.

• 2:29Speaker 02

  Spoiler: They didn't find anything. There was no Martian NPR.

• 2:32Regina Barber?

  But humans have continued to look for signs of intelligent life in the universe. And James says we've barely scratched the surface.

• 2:40Speaker 02

  If the thing we were looking for was the size of the ocean, so far, as of about 2000, we had looked at a pint glass of water, compared to the volume of the ocean.

• 2:49Regina Barber?

  Wow, wow. And that's where our scientific efforts have mostly been, looking at radio transmissions from outer space. SETI has looked for spikes, terps, and unusual things from radio telescopes for about 60 years. But James and others think there's so much more data to sift through outside of these radio signals. So today on the show, a legitimate look at the search for intelligent life in space, the ways we look, and how scientists are taking the search to the next level. I'm Regina Barber, and you're listening to Short Wave, the science podcast from NPR.

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• 4:49Regina Barber?

  Okay, James, let's just like get into it. There's this equation that people throw around. It's an equation that tells us the likelihood that there's alien life that could send us a signal. It's called the Drake Equation. Can you break that down for us?

• 5:03Speaker 02

  So the Drake Equation is the number of stars times the fraction of those stars that should have intelligent life. It's capable of sending us signals. In its simplest form, it's the number of stars times the fraction of stars that have NPR.

• 5:19Speaker 02

  Or something like that. Now, what goes into that NPR term? Well, you have to have a planet. It has to be at that Goldilocks distance from its parent star. It has to have water. It has to have all the ingredients that we know and many of the ingredients we don't know. And there's a lot we don't know about what drives life. So the last 25 years, there has been a really big surge in this field called astrobiology.

• 5:41Regina Barber?

  Right.

• 5:42Speaker 02

  And they've tried to answer the parts of that equation. Like, well, how many stars have planets? Is it every star? Is it only stars like our sun?

• 5:52Speaker 02

  So now we know that on average, every star roughly has at least one planet.

• 5:56Regina Barber?

  Wow.

• 5:57Speaker 02

  At least one rocky type planet on average.

• 5:59Regina Barber?

  Wow.

• 6:00Speaker 02

  That means.

• 6:00Regina Barber?

  That's so many.

• 6:01Speaker 02

  That means there's so many. That means that for a galaxy of more than 100 billion stars, that means we have at least 100 billion planets to search. And even still, even after 25 years of astrobiology, we still don't know. There still is enough unknowns in that equation that we don't know the answer still. So there's a lot of work to be done.

• 6:21Regina Barber?

  And the Drake equation doesn't take into account time. I personally was like, OK, the universe is like 13.8 billion years old. Our sun is like around 4.6 billion years old. I feel like there could have been civilizations that were have come and gone.

• 6:36Speaker 02

  I mean.

• 6:37Regina Barber?

  By that point, but that equation doesn't take that into account.

• 6:39Speaker 02

  You can write it in a way that does, right?

• 6:41Regina Barber?

  Oh, OK.

• 6:42Speaker 02

  You can write it in such a way that how many civilizations arise? And what's the likelihood that they live long enough to develop radio telescopes and astronomy? And space travel perhaps? So you can write the equation sort of in different ways. It's not a strict equation in the same way as Einstein's theory of relativity. It's an equation that gives us kind of an outline for how to frame the problem. It's more of a illustration.

• 7:05Regina Barber?

  OK, so this illustration, this equation comes from a man who kind of began what led to like modern SETI.

• 7:12Speaker 02

  So really, what we consider the beginning of modern SETI is 1960. So Frank Drake, who some people know from the Drake equation, which tries to quantify what's the likelihood that we're alone in the universe. He was actually the pioneer where he had time on a radio telescope for good bread and butter astronomy reasons. At this point in 1960s, people are looking at galaxies and gas and dust in the interstellar medium. And radio telescopes are a new technology still. And he decides to point it at a couple of nearby stars to quote unquote, "listen", with the intent of looking for, again, chirps or pulses or some kind of transmission. He doesn't find anything, but he starts what he calls Project Ozma, named after the Wizard of Oz.

• 7:54Regina Barber?

  Oh, my gosh.

• 7:55Speaker 02

  Right.

• 7:55Regina Barber?

  OK, cool.

• 7:56Speaker 02

  And he starts to look for signs of, you know, transmissions, intentional transmissions from technology. And this is really the beginning of what we call SETI, the Search for Extraterrestrial Intelligence.

• 8:07Regina Barber?

  OK, and since SETI has like been officially operational, that's like 1985, we haven't found anything, right? But you mentioned that analogy that like we've only searched like the equivalent of a pint glass of water versus like the ocean that is the entire sky.

• 8:24Speaker 02

  We've done a lot of work since. So my estimate a couple of years ago was we've pushed that from a pint glass of water to maybe a hot tub.

• 8:31Regina Barber?

  OK, that's not bad.

• 8:33Speaker 02

  Yeah, that's that's massive progress, right? There's a lot of pint glasses in a hot tub.

• 8:37Regina Barber?

  Yeah, yeah. And but you're an astronomer, right? That looks at stars, not radio signals. And but you're working with SETI. So like, how are we going to search more of the sky? Like, get more than a hot tub in an ocean of water?

• 8:50Speaker 02

  Right, so I am an optical astronomer. By training, I'm a stellar astronomer. I look at stars with sort of classical optical telescopes that you would look through with your eyes and we attach digital cameras to. This is not the area that SETI has worked on for like 60 years. But we have put a lot of effort into it for lots of other astrophysics and astronomy reasons because stars are bright and there's fun physics. There's lots to learn there in the cosmos. And that's what I spent 20 years doing. And then this realization that we're putting all this money into optical astronomy, why aren't we looking for maybe the most interesting thing? Looking for life, looking to answer these questions about whether or not we're alone. My inner eight-year-old, my inner Star Trek nerd, started putting this together that we should use the data that we have and try to figure out

• 9:35Speaker 02

  how to pull the knowledge from 60 years of radio astronomy and apply it into this optical, visible light astronomy. My hope in pushing this from the radio into the visible light, into the infrared and other domains of astronomy that are so active is that we can actually push this from a from a hot tub to maybe an Olympic swimming pool.

• 9:56Regina Barber?

  Okay, so there's even better technology on the horizon to make the search even more comprehensive. I'm thinking of the massive Vera Rubin telescope being built in Chile right now. How do you see this telescope impacting how we look for life outside of Earth?

• 10:11Speaker 02

  So just yesterday, the very first-

• 10:13Regina Barber?

  Yesterday being January 14?

• 10:14Speaker 02

  Right. The very first commissioning image from the telescope from their engineering camera was shown.

• 10:20Regina Barber?

  Wow.

• 10:20Speaker 02

  And it's beautiful, and it's early days, but the telescope is now being tested and everything is being aligned. So it has gone from 20 years of development to a reality. This telescope, it's going to sit in Chile and for 10 years, create this mosaic movie of the sky. And it's going to watch the sky every night with the world's largest digital camera, built in California, shipped all the way to Chile. This camera is the size of a small car. It's massive, powerful camera, attached to an eight and a half meter telescope. So an enormous piece of glass, one of the 10 biggest pieces of glass ever built. It's incredibly powerful. And what you get for all that is a sample of more than 10 billion

• 11:05Speaker 02

  stars. The best samples of stars so far are 1 to 2 billion. We're going to push that up to 10, maybe 15 or 20 billion stars in our galaxy.

• 11:14Regina Barber?

  Wow.

• 11:15Speaker 02

  That's a total transformational shift. It's going to be something that really is a tide that raises all the astronomical boats. We're going to see the binary stars and the supernova. We're going to double the known number of asteroids and comets in the solar system-

• 11:30Regina Barber?

  Important.

• 11:30Speaker 02

  -in the first year.

• 11:32Regina Barber?

  You're getting me excited.

• 11:33Speaker 02

  Good.

• 11:35Regina Barber?

  But James, all these decades of searching, we really haven't found anything. How are you this patient? How do you keep yourself inspired that this is going to be this new era of SETI?

• 11:48Speaker 02

  Because success doesn't depend on finding something, right? The search itself is, the journey is the thing that we're after.

• 11:55Regina Barber?

  Wow.

• 11:56Speaker 02

  It may take, and this is what I tell my students, it may take 1,000 years to know the answer to this question. We've only just begun looking. 1960 was not that long ago.

• 12:06Regina Barber?

  Right.

• 12:06Speaker 02

  And even if we do all of our work and we get it up to a swimming pool as compared to the ocean, that's only one swimming pool against a very big ocean of possible parameter space that we're looking. It is going to take a long time to put this story together and to be sure that we have found something or that we haven't, that we're alone or that we're not. That's OK. The advent of photography and computers means that our data is forever. So a star that doesn't do anything, that was seemed boring to us for 10 years, 25 years from now, it might do something interesting. And if we don't have that record, if we don't do our work, then they don't stand a chance of finding anything.

• 12:49Regina Barber?

  James, thank you so much for coming here and really making me excited about searching for life in space.

• 12:59Speaker 02

  If we all pitch in, if we all do a little bit, like we did.

• 13:03Regina Barber?

  Like we did with those screensavers.

• 13:04Speaker 02

  With the screensavers when we were kids. If our entire community of astronomers and scientists and the public come along with us, we're going to make a dent.

• 13:14Regina Barber?

  This episode was produced by Burleigh McCoy and edited by showrunner Rebecca Ramirez. Tyler Jones checked the facts. Kwasi Lee was the audio engineer. Beth Donovan is our senior director and Colin Campbell is our senior vice president of podcasting strategy. I'm Regina Barber. Thank you for listening to Short Wave from regular old NPR, not Martian NPR.

• 13:45Regina Barber?

  Stay tuned for the following announcements and messages from our sponsors.

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