Are We Alone? with Jill Tarter

Summary

StarTalk Radio: Are We Alone? with Jill Tarter

Host: Neil deGrasse Tyson
Guest: Jill Tarter (Co-founder, SETI Institute)
Co-host: Matt Kirshen
Date: August 19, 2025

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Overview

In this Cosmic Queries edition of StarTalk, Neil deGrasse Tyson and comedian Matt Kirshen welcome Dr. Jill Tarter—pioneer in the Search for Extraterrestrial Intelligence (SETI) and inspiration for Carl Sagan’s Contact. The discussion covers humanity's centuries-long quest to discover life beyond Earth, the technical and philosophical challenges of detecting alien intelligence, and listener questions about ethics, technology, and the daunting odds of making contact.

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Main Discussion Points & Insights

1. Jill Tarter’s Background & Early Work

• Brown Dwarfs Discovery:
  • Jill Tarter recounts her doctoral thesis on "brown dwarfs"—objects more massive than planets but too small to sustain hydrogen fusion like regular stars.
    • “My thesis was about what I call brown dwarfs. Stars that are too low mass to stably fuse hydrogen at their cores.” (03:26, Jill Tarter)
• SETI Involvement:
  • By chance, Tarter was recruited to early SETI efforts because of her computer programming skills, despite the infancy of digital technology.
    • “I learned how to program the first computer that we ever had on our desktop…you had to program each step in octal. Right. So you had to set all the ones and zeros by hand.” (05:45, Jill Tarter)

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2. SETI’s Focus on Technological Intelligence

• Search for Techno-signatures:
  • SETI is primarily searching for evidence of advanced civilizations—in particular, those that leave detectable technological traces (e.g., radio signals), not just biology.
  • “We're looking for something, someone that can modify its environment in ways that we could sense over the vast distances between the stars.” (10:21, Jill Tarter)
• Limits of SETI’s Technology:
  • The search is naturally limited by the capabilities of current equipment; intelligent civilizations lacking radio or powerful tech would be invisible to us.
  • “If you found an Earth that had a Roman Empire…you would pass them by saying, nothing here. Keep walking.” (11:23, Neil deGrasse Tyson)

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3. Why Radio Waves?

• Physics of Interstellar Communication:
  • Radio waves pass through cosmic dust, unlike visible or infrared light, making them optimal for communication across the galaxy.
    • “Radio...they basically don't see the particles, they don't see the dust, and are not absorbed by it…We’ve been looking at the center of the galaxy at radio waves from very early times in this scientific discipline.” (16:11, Jill Tarter)
• SETI’s Assumptions:
  • The search presumes alien civilizations would discover and use similar physics, at least at some point in their development.
    • “Any aliens would have to know enough astrophysics to conclude that radio waves would penetrate space in the way other bandwidths wouldn't.” (17:14, Neil deGrasse Tyson)

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4. How Much Have We Searched?

• The ‘Glass in the Ocean’ Analogy:
  • Jill Tarter addresses the scale of humanity’s search for alien signals, using her famous analogy:
    • “All the searching we'd done to date was as if we said, ‘oh, we're going to look for fish in the ocean’ and what we did was take an 18 ounce glass and dip it in the ocean and take a look and say, ‘are there fish in there?’…You have to look harder. That's where we are.” (18:59, Jill Tarter)

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5. The Significance of Contact

• Existential Meaning:
  • The discovery of another technological civilization would imply hope: advanced societies can survive their own adolescence.
    • “If you were to succeed, you would by inference, know that it's possible to outlive your technological infancy and to have a long future.” (20:02, Jill Tarter)

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Memorable Quotes & Notable Moments

• On the Intersection of Bias & Technology:
  • “You can't search for intelligent life that does not have technology.” (11:23, Neil deGrasse Tyson)
• On the Challenges of SETI:
  • “Might have. But on the other hand, if you're stubborn, you might have turned that around and said, wow, this is one of the most interesting questions that humans can ask about themselves and their place in the cosmos.” (20:02, Jill Tarter)
• On Disclosure:
  • “I'm going to tell the world about what we found and at least my interpretation of what that means. But the world is going to decide how they're going to react.” (22:52, Jill Tarter)

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Key Listener Questions & Timestamps

• What happens if we find alien life? (22:39)
  • Tarter emphasizes transparency but says humanity’s reaction is unpredictable.
• Arthur C. Clarke’s “Equally Terrifying” Quote (23:30)
  • Tarter finds both possibilities “extremely significant,” noting that finding others offers hope, while our solitude is daunting.
    • “Both are extremely significant. One is not so hopeful in terms of the continued existence of life on Earth. The other is…incredibly exciting and impactful to know.” (24:19, Jill Tarter)
• What does SETI actually ‘listen’ for? (25:13)
  • SETI looks for narrowband signals that nature cannot easily replicate, indicating artificial origin.
    • “What we use instruments to try and detect is the kind of emissions that nature can't do…narrow band transmissions.” (26:25, Jill Tarter)
• Could aliens detect our TV/radio signals? (30:03)
  • Likely only the carrier signal, not the actual content, is detectable from afar. (30:54, Jill Tarter)
• Should we send signals or build structures to get noticed? (34:20; 35:47)
  • Passive listening is far cheaper and less disruptive than actively transmitting; funding and practicality prevent large-scale active efforts.
    • "If everybody's listening and nobody's talking, we're not going to succeed." (36:46, Jill Tarter)

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Ethics, Funding, & Future Speculations

• Ethical Guidelines for Contact (38:11, 40:22):
  • SETI follows international principles for data verification/announcement, but further ethical decisions would likely be shaped by religion and geopolitics, especially in the case of intelligent (not microbial) life.
    • “The ethics are going to come from probably the religious entities across the planet, and those are different and they have different perspectives.” (40:22, Jill Tarter)
• International Competition:
  • The Chinese have the world’s largest radio telescope; first contact might not be an American discovery. (43:17)
• Technological Limitations & Future Physics (45:30):
  • While SETI searches for radio signals, Tarter acknowledges we may be limited by our own physics—not ruling out the possibility of undiscovered means of communication.
    • “We think about it, but we don't know how to do it right.” (46:34, Jill Tarter)

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Probability, The Drake Equation, and The Odds

• Co-temporality Problem (48:01):
  • SETI’s odds of detection depend on both the lifetime of technological civilizations (L in the Drake Equation) and the overlap of their communicative phases with our own.
    • “Unless L…is large, there's not going to be any success. There won't be any overlap.” (48:21, Jill Tarter)
• Drake Equation (49:33):
  • Describes the variables involved in estimating the number of detectable civilizations.
    • “The number of technological civilizations in the Milky Way galaxy…can be estimated by taking the rate of star formation…multiplying that…by the average longevity of the technologies…” (49:33, Jill Tarter)
• Current Best Guess:
  • Civilization length (L) is at least about a century (our own radio era), but the upper limit is unknown.

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On UFOs and Recent Congressional Hearings

• SETI’s Involvement in UFO Discourse (51:59):
  • Tarter maintains that thorough, ordinary explanations exist for most reported phenomena.
    • “If you can explain the evidence with ordinary means and ordinary physics…then, you know, go home. Occam’s razor.” (53:02–53:37)

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Fun, Tone, and Pop Culture References

• The Inspiration for Contact’s Ellie Arroway:
  • Sagan's protagonist was based on Tarter: “Carl was a member of our board of directors. He wrote a book about a woman who does what I do.” (13:29, Jill Tarter)
• Humorous Banter:
  • Discussing whether comedians would expect aliens to have their own comedians or if we’d be the “vegetables” in alien culinary culture. (40:00, 55:57)
• Running Joke:
  • Neil offers to push for a ‘volunteer tax’ on alien movies to fund SETI. (54:29)

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Final Thoughts

• Persistence & Hope:
  • Despite daunting odds and slow progress, the search itself is among humanity’s most profound scientific quests. The hope is, as Tarter summarizes, “When we succeed, we'll know we've done the right thing.” (29:55)
• Promise of Transparency:
  • Jill Tarter assures: “When we make contact, you will know. I'm going to tell the world.” (22:52, 55:06)

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[End of summary]

Transcript

[Neil DeGrasse Tyson]

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[Neil DeGrasse Tyson]

So, Matt, we got the Top Dog at SETI on StarTalk to catch us up on all. It's Jill Tarter. We've heard of her.

[Matt Kirshen]

The Alien Whisperer. Can you call her the Alien Whisperer? She's the main alien person we went to.

[Neil DeGrasse Tyson]

The number one alien person coming up on StarTalk, the alien whisperer, Jill Tarter. Check it out. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil DeGrasse Tyson, your personal astrophysicist. I got with me my co host, Matt Kirschen. Matt, how you doing, man?

[Matt Kirshen]

I'm very good, thanks, Neil. How are you doing?

[Neil DeGrasse Tyson]

Yeah, we caught up with you. You're in port in Bermuda. Why didn't you invite us for that?

[Matt Kirshen]

I am. I'm in a very small cabin on a cruise right now. So I'm on tour right now. I'm doing some lovely theater shows with Sarah Milliken, who's a fantastic UK comic. And I'm doing some headline spots off the back of that. And then in between those, I'm on a boat. So.

[Neil DeGrasse Tyson]

On a boat? Why not? You know what I'm talking about today. It's a Cosmic queries. We're catching up with this search for alien intelligence. We should do at least two of these a year because that's what the public's appetite surely wants. There's so much misinformation or speculative information and I think our audience expects us to at least anchor what's going on. And that's definitely what we intend to do. Today we're reaching into the depths of the search search for alien life and finding an old colleague of mine from way back, one of the founders of the SETI Institute Search for Extraterrestrial Intelligence. And that would be none other than Jill Tarter. Jill, welcome back to StarTalk.

[Jill Tarter]

Well, hi Neil. It's great to talk with you again.

[Neil DeGrasse Tyson]

Not many people know that you cut your teeth studying stars. Correct. You, a co discoverer of a just remind us of that discovery. Just to put your early chops on.

[Jill Tarter]

The map here, my thesis was about what I call brown dwarfs. Stars that are too low mass to stably fuse hydrogen at their cores.

[Neil DeGrasse Tyson]

Don't we just call those planets?

[Jill Tarter]

No, these are a little different. They're a bit more massive than Jupiter. And I was trying to figure out, because I wanted to go looking for them. We thought, thought at that time that a problem that we had that we called the missing mass, where the mass of the galaxy that we inferred from dynamical motions of the stars differed from the mass that we calculated when we added up all the individual masses of clouds of gas and stars. And so there was this Ms. Mass. And I thought that stars that were too small to fuse hydrogen and burn normally might be what could explain that missing mass and so could be hidden in those objects.

[Neil DeGrasse Tyson]

Yeah.

[Jill Tarter]

Yes. And the thing was I tried to put an atmosphere on my model of the star so that I could tell what the temperature or the color of that star would be to help observers go looking for them. And I couldn't do it. So I couldn't get a color. And I called them brown dwarfs. To Edmond Land, brown is not a color. So they're brown dwarfs. And it took us 25 years to find the first one. But now we know they're very plentiful.

[Neil DeGrasse Tyson]

So who would have thought that there was an entire category of object living there between the highest mass planets and the lowest mass stars. It's easy to just discounted that as it's a fuzzy boundary. Remind us what got you interested in aliens.

[Jill Tarter]

It was a very fortunate accident. When I was doing my thesis, I learned how to program the first computer that we ever had on our Desktop. Now, it took two people to get the computer up on the desktop, but once it was there, it was ours. Right. And so you had to. There was no language, nothing like Fortran or anything like that. You had to program each step in octal. Right. So you had to set all the ones and zeros by hand. And I learned that skill. I thought it was great fun as a puzzle. And so when I was asked to join Stuart Boyer and X Ray Astronomy and his group at Berkeley who were interested in looking for signs of someone else's technology, I was asked because I knew how to program this computer and that was the only tool we had to use. And so I did it. And it was again, a fortunate accident.

[Neil DeGrasse Tyson]

Well, as any good collaboration unfolds, every person in that collaboration brings their unique abilities, right?

[Jill Tarter]

That's right. And they wanted me because I could program this computer. And so I often tell young people to, to get some skill, to find something they like to do and then get better at it than anybody else. So then they have a tool set that they can go shopping to look for programs and problems that they're interested in solving.

[Neil DeGrasse Tyson]

And people will beat a path to your door for that expertise. That's right, yeah.

[Matt Kirshen]

And to be clear, you don't still program in ones and zeros. You go to the languages now?

[Jill Tarter]

No, no. Now there are all kinds of languages that you can use and much better computers.

[Neil DeGrasse Tyson]

Obviously, biologists would be intrigued by any kind of life at all discovered on anywhere, you know, microbial even. But your sights are set to even higher goals than that. If I can rank them in this way, maybe that's kind of a bias, I guess, a brain bias. But you're not just looking for any life, you're looking for intelligent life. And what's odd is there, you know, you get this sense that people think that somehow we don't want to know if there's intelligent life or that it's being suppressed or that it's being. It's like nothing could be farthest from the truth. And given the efforts that we as a community have put in, especially focused at the SETI Institute, I'm just surprised by this overall sense that somehow people think it's going, there's some kind of COVID up. Have you had to, I presume you've had to contend with this.

[Jill Tarter]

Well, at one point I had to talk to a military panel and promise that our SETI algorithms and antennas would not be able to detect frequency hopping spread spectrum signals, because I believed it. And then it turned out when we Got on the air. Yeah, we could see those too.

[Neil DeGrasse Tyson]

Are they saying they restricted your bandwidth access because they were doing their own searching?

[Jill Tarter]

No, they were curious about what I might see, what we, with our equipment and software might see that they weren't advertising that they were doing.

[Matt Kirshen]

So you were searching not just for extraterrestrial intelligence. Burp. Accidentally bought for military intelligence.

[Jill Tarter]

Yeah, Right. But, you know, I, I literally, I said, no, no, we can't see that. Not the way we written our software. No, it turned out, you know, our software was better than I thought.

[Neil DeGrasse Tyson]

And so how do you go about thinking this up? That surely takes a bit of hubris, chutzpah to just declare that if there's intelligence out there, we would be able to communicate with it. We can't communicate meaningfully with other animals here on Earth with whom we have DNA in common. Even a chimpanzee. You're not hanging out with a chimp. Say, let's go have a beer later. Oh, sure, Jill, I'm good with that. No, where do you. Where do you get your confidence that this even would work at all?

[Jill Tarter]

What we can do with our equipment and our software limits what we could possibly find. And so we're looking for something, someone that can modify its environment in ways that we could sense over the vast distances between the stars. And it's a limited subset of what possibilities there are, because we have the equipment of the 21st century, which is better than the equipment of the 20th century, but not necessarily all powerful. So we can look for certain kinds of, what we call techno signatures that would indicate somebody is doing something that nature can't do.

[Neil DeGrasse Tyson]

You can't search for intelligent life that does not have technology. So if you found an Earth that had a Roman Empire, you know, their version of a Roman Empire, that certainly, that's advanced. Certainly they're intelligent, but they don't have radio telescopes. So you would pass them by saying, nothing here. Keep walking.

[Jill Tarter]

Yes, with the technology that we have today. But ChatGPT and all the other large language models are going to be able to do some incredible things in the future. In particular, I think the interesting thing is that whereas any particular search technique looks at certain phenomena at certain frequencies in a certain amount of time, the chatbots will be able to combine or look at simultaneously data sets collected for completely different reasons across the spectrum and across technologies, and might be able to find some correlations that we were totally unaware of.

[Neil DeGrasse Tyson]

You're developing a dependence on AI to take you to that next step that you wouldn't otherwise be able to accomplish. Remind me why radio waves is the bandwidth of choice? Because that was clearly displayed in Carl Sagan's novel Contact, later becoming the film, the hit film with the character Ellie Arroway. She was a radio astronomer, basically who is listening for looking for radio signatures out there in space. And rumor has it that Carl Sagan knocked on your door a few times to try to get some insights into this character. Can you confirm or deny those rumors?

[Jill Tarter]

Carl was a member of our board of directors. He wrote a book about a woman who does what I do.

[Neil DeGrasse Tyson]

There it is.

[Matt Kirshen]

Perfectly put. Perfectly put.

[Jill Tarter]

That character is Carl. What comes across as Ellie Arroway is actually Carl and his musings and his thinkings and his. It's probably too long to go into, but basically Carl would have loved to be able to have one more conversation with his deceased father. And that drove a lot of the thinking.

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[Jill Tarter]

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[Matt Kirshen]

I'm Joel Cherico and I support StarTalk on Patreon. This is StarTalk with Neil DeGrasse Tyson.

[Neil DeGrasse Tyson]

Why radio waves and not visible light or any other band of the spectrum?

[Jill Tarter]

The fact is that space is not empty, but there are clouds of gas and dust out there between the stars. And infrared or optical wavelengths are absorbed by these clouds and they can't travel very far through the galaxy. We've never seen the center of the Milky Way galaxy at optical wavelengths because it's just too dusty. But radio. The wavelengths of radio waves are not anywhere near the size of the dust particles in These clouds. And so they basically don't see the particles, they don't see the dust, and are not absorbed by it. So we've been looking at the center of the galaxy at radio waves from very early times in the, in this scientific discipline.

[Neil DeGrasse Tyson]

Any aliens would have to know enough astrophysics to conclude that radio waves would penetrate space in the way other bandwidths wouldn't. So we're assuming they'd be on exactly the same track we are in our learning and understanding of the galaxy.

[Jill Tarter]

At least at some point in time. They are or were. Right. Because they could in fact create technologies that outlast their civilization. There are a couple of spacecraft in orbit around this planet that will be there 10 million years in the future. Their orbits will not decay. You know, it's a really interesting question about whether what we're looking for and what is being transmitted overlap in time in this 10 billion year history of our galaxy.

[Neil DeGrasse Tyson]

That's part of the parameter space that you speak of so dauntingly. Right. Because you can search in frequency even within the radio wave bandwidth. You could be sending a signal or listening, trying to observe a signal in one band of radio waves. But then there's another bandwidth within the radio waves that could be where the action is and you would miss it. And maybe they sent a signal that got here 100 years ago instead of today. Cause it is light travel time for wherever it is. What's this analogy you gave to the ocean? It was the best thing I ever heard. What was it about how much we have searched thus far for aliens? Cause you hear people say, well, we've looked for aliens and we haven't seen any. So there probably aren't any. And what's your reply to them?

[Jill Tarter]

My reply is that we've hardly begun to look. At one point when Seti turned 50 years old, as a discipline, I did a calculation that indicated that all the searching we'd done to date was as if we said, oh, we're going to look for fish in the ocean. And what we did was take 18 ounce glass and dip it in the ocean and take a look and say, oh, are there fish in there? Well, there are fish small enough to have fit in that glass, but if you didn't see any, you'd hardly make the conclusion that there were no fish in the ocean. You just simply say, you have to look harder. That's where we are. We can do so much, but we can't do everything. And we are always looking for new ways.

[Neil DeGrasse Tyson]

If you had told me that calculation when I was just coming on and I wanted to be like a SETI researcher. I would have given up in that moment. I would have said, okay, I'm taking up another job.

[Jill Tarter]

Might have. But on the other hand, if you're stubborn, you might have turned that around and said, wow, this is one of the most interesting questions that humans can ask about themselves and their place in the cosmos. And if you were to succeed, you would by inference, no, that it's possible to outlive your technological infancy and to have a long future. Because if the future isn't long for technologies in general, there aren't ever going to be any two that overlap in time. But if you find something, you know that there's a long, you know, path ahead for us potentially, we don't necessarily have to destroy ourselves.

[Neil DeGrasse Tyson]

So that's a, that's a, that's a profound inference from such a simple bit of information you would glean. Let me see if I can restate it. So make sure I understand it. You're saying if technologically proficient civilizations lasted only one or two centuries and then they rendered themselves extinct, something bad happens, or it took them that long to even get to that point, and then it doesn't last long. Then when you come upon a planet at a random time in its own evolution, because it could have just been born a million years ago, or a billion or 10 billion, you don't know if you're hitting it at exactly that time. And so if everybody only were short lived, nobody would be talking to anybody. And it would give us very little hope for the future of our fingerprint in this world. Is that a fair characterization of what you just said?

[Jill Tarter]

That's correct. But if you don't go looking for it in as many ways as you possibly can, you'll never find it.

[Neil DeGrasse Tyson]

You're an astrophysicist posing these questions, presuming that they have astrophysical tools. And I'm wondering, if comedians were doing this search, would they presume that the other civilization would have comedians? Is this a natural extension of our own bias?

[Matt Kirshen]

I mean, I don't know about that, but I definitely know that I've played some gigs where I've wondered whether there's any life out there.

[Neil DeGrasse Tyson]

Intelligent life. Intelligent life, definitely.

[Matt Kirshen]

Intelligent life, definitely. Definitely. Is there anything there?

[Neil DeGrasse Tyson]

Let's head out to our cosmic queries about now. You've collected them, Matt?

[Matt Kirshen]

Yeah, absolutely. As always, Betty from Maine has asked, if you find life outside of Earth, what are you going to do with it?

[Neil DeGrasse Tyson]

Yeah, Jill, are you going to conquer it and Enslave it and colonize it. What are you going to do?

[Jill Tarter]

Me? I'm going to tell the world about what we found and at least my interpretation of what that means. But the world is going to decide how they're going to react. It's not going to be me that makes that kind of decision.

[Neil DeGrasse Tyson]

And what confidence do you have that that response would be what you would consider appropriate?

[Jill Tarter]

I don't know, Neil.

[Neil DeGrasse Tyson]

That's not very helpful. Come on, Jill.

[Jill Tarter]

Oh, come on. Given the politics of our country, I don't know. But all I can say is that you'll know what I know.

[Matt Kirshen]

So Atticus from Soddy Daisy, Tennessee, who is 10 years old, says the quote from Arthur C. Clarke. Two possibilities exist. We are either alone in the universe or we are not. Both are equally terrifying. This keeps me up at night in an amazing not scary way. Please give your thoughts on the idea behind the quote.

[Neil DeGrasse Tyson]

Oh, Atticus, are 10 year olds allowed to have these kind of profound thoughts?

[Matt Kirshen]

I know.

[Neil DeGrasse Tyson]

Also going to bed after the playground or something.

[Jill Tarter]

Or at least not having to stay up at night worrying about it.

[Neil DeGrasse Tyson]

Well, Atticus, we all share that profundity of thought that delays your slumber. And Jill, let's hear from an expert here. Jill, are both terrifying to you?

[Jill Tarter]

Both are extremely significant. One is not so hopeful in terms of the continued existence of life on Earth. The other is something that would be incredibly exciting and impactful to know because if you know that somebody else has made it through this very precarious technological phase that we're in, then there's an answer, there's some way to do it. And that inspires me anyway to go looking harder for that answer here on Earth. Yeah, yeah, yeah. Somebody else made it through. We can too.

[Neil DeGrasse Tyson]

Okay, I like that.

[Matt Kirshen]

Well, while we're talking about the actual process, it's a pretty top level question. Vincent Thomas says, what exactly do you listen for out there in the stars?

[Neil DeGrasse Tyson]

And just to be clear, I just want to like, just. The radio telescopes are like other telescopes. They're detecting light. So somewhere in the decades past, people have equated a radio telescope with listening to sounds. And people think we're listening for sounds. And they did that in the movie Contact where Ellie Arroway's listening to her data. But these are observations of radio light. Correct. And we're just being loose when we say we're listening. That's like saying, let me listen to the sun and just like look at it. Okay. No, you're like receiving light.

[Matt Kirshen]

Martin leblanc from Montreal does End the question with and Neil, for this episode, I dare you to change your saying with keep listening up.

[Neil DeGrasse Tyson]

Oh, okay. Maybe I'll do it just for him. Okay, but Jill, let's get your reaction to that.

[Jill Tarter]

What we use instruments to try and detect is the kind of emissions that nature can't do. And that generally means some kind of transmission that is very compressed in frequency, because nature doesn't do that. Nature's emissions come from gazillions of molecules and atoms, each of which is vibrating or rotating and emitting a very specific frequency. But all of the atoms and molecules are moving with respect to one another, so that the ensemble signal is Doppler broadened. So each of these individuals transmissions from a molecule or an atom gets added with all the other molecules and atoms that are all moving relative to one another, and you get a broad signal. But technology can get around that. We have means with lasers and masers of compressing a signal into a single frequency or a small range of frequencies, what we call narrow band transmissions. And either we'll learn something unexpected about nature and find that nature can do this job and trick as well as we can, or better, or we'll find evidence of the technologies that we're looking for.

[Neil DeGrasse Tyson]

And so it's not just that the signal exists. You might want or expect or hope that signal to also contain information within it. Again, in the film Contact, the signal was, at least in the film version, it was prime numbers. I think it was right, whereas I think in the novel it was digits of PI perhaps, but might be confusing my memory. But within the signal, there was information. So can you decode if you did find the narrowband, or do you have a next layer analysis to see what they might be trying to tell us?

[Jill Tarter]

Well, again, that's one of the reasons that I want to tell everyone what we may have detected and what we've interpreted, because there are far better code breakers out there than me. And so we'd be eager to engage the intelligence of the rest of the world to help us understand any information. And one thing that I should mention is, although we talk about listing and we talk about radio, and I've argued that other frequencies don't travel as far through the galaxy as the radio wavelengths, we are also trying to take the techniques that we have and push them into the infrared and the optical for sources that are closer by.

[Neil DeGrasse Tyson]

All right, well, it sounds like you're on top of that situation.

[Jill Tarter]

Well, who knows? I'll let you know. When we succeed, we'll know we've done the right thing when we succeed.

[Matt Kirshen]

So Jonas Dravland says, good day, doctors and lords. Jonas from the Appalachian foothills of North Carolina. If there were a SETI like organization on a distant star system, how close would they need to be to detect us? Would they be able to watch I Love Lucy? And should they expect to pick up their domestic radioactivity? Or are we basing our search on the presumption that they are sending signals intended to advertise their existence?

[Neil DeGrasse Tyson]

Oh, yeah. So I'd love that, because our earliest radio signals are just our earliest escaped television broadcasts right now, going into 100 years, you know, 80. How many years ago? Early. Well, I Love lucy, it was 1950s and 60s or the honeymooners. Are they going to learn how men and women interact on earth from those.

[Matt Kirshen]

Two shows, 1950s TV and earlier radio?

[Jill Tarter]

I think what might be detected is not the information content of the television program, but the existence of the carrier signal that transmitted that information. Or maybe once we detect evidence of someone else's technology, they're going to explain and we translate it somehow. They're going to explain to us why Lucy and Ethel shouldn't have had subservient roles.

[Neil DeGrasse Tyson]

Or Alice and the Honeymooners. Yeah, all of the above. Catch us up. Just briefly take a break from the questions and ask you, what telescopes do SETI are in the arsenal of SETI's control?

[Jill Tarter]

Well, we have a special telescope that we've developed for working in the infrared and optical that we call optical SETI or laser seti. I should say. These are special instruments that we've developed. Otherwise, what we use is existing telescopes that are part of the astrophysical realm. And we can essentially piggyback on the signals being detected by those telescopes which are looking for other things in other ways. But we can carve out a piece of that signal without affecting the primary observer, and we can analyze it looking for these technosignatures. So it's really anything out there that's looking at the universe. We are eager to replicate their data so that we can analyze it in a different way.

[Neil DeGrasse Tyson]

And the SETI Institute is mostly privately funded, is that correct?

[Jill Tarter]

Yes. Yes, we do. Well, I shouldn't say that SETI at the SETI Institute is privately funded, but we have over 100 PhDs at the SETI Institute who are looking in many different ways to discover life beyond Earth. These programs are typically funded by the National Science foundation and NASA. So we do have government funding. And we're very nervous right now about what's going to happen.

[Neil DeGrasse Tyson]

Science funding in many realms Today feels like, oh, science is just optional. Other things are more important. There's been a shift in priorities which will have consequences that people do not. We foresee, but the general public doesn't really, given how much of modern civilization pivots on the moving frontier of science. But. Okay, let's keep going. Matt, what else you got?

[Matt Kirshen]

Uikia from India living in California says, how detectable is Earth as a life harboring planet from a nearby star system? Should we put any large visual structures around Earth or Jupiter so that intelligent aliens can detect them as non naturally occurring structures when they monitor the transits around the sun? Thank you to SETI and StarTalk for trying to answer the most fundamental questions and promoting scientific thinking.

[Neil DeGrasse Tyson]

Oh, cool, cool. Yeah. We do all we can to get noticed.

[Jill Tarter]

No, we're not. Because there are other priorities for funding to do the kinds of things that are being suggested in this question is not cheap to build structures to modify orbits of asteroids or planetesimals or. That's all really difficult and expensive. And while it might happen for other reasons, such as mining rare earth elements which we are depleting on this planet, it's not likely anytime soon to be done specifically for attracting the attention of any technologies out there. It's just unfortunately not a high enough priority.

[Neil DeGrasse Tyson]

Jill, I remember a zillion years ago I asked you a question after a colloquium you gave, and you gave the cleanest, simplest answer to a question similar to this one, which was I asked, why are we spending so much time just listening for aliens? Why don't we just blast the universe with our own signals? And at the time, what you said was it cost almost nothing to just passively listen for signals. So you can get away with that without breaking the piggy bank. If you want to actively send signals out, that's orders of magnitude way more money than what it would cost to just listen. Because I thought it was unfair that if everyone were doing what we're doing, then the whole universe would be listening for other aliens and no one would be transmitting and everyone would conclude there's no other life, intelligent life, in the galaxy.

[Jill Tarter]

That's right. If everybody's listening and nobody's talking, we're not going to succeed. But another impediment, if you wish to this idea of deliberately transmitting to make ourselves known to the cosmos is the fact that if we do that, that's going to interfere with an enormous number of other disciplines and searches and technologies. I mean, it probably would mess up your GPS just enormously, right? Yes. Cost is the major impediment, but there are unintended consequences of doing powerful transmissions.

[Matt Kirshen]

Well, while we're talking about ethical considerations, Hugo Dart from Rio de Janeiro with Hugo's seven year old daughter, Olivia, who's also a big fan of StarTalk. Ask what parallel, if any, exists between how we treat animals and vegetable species on Earth and ethical parameters we can establish for dealing with alien life. And I'm just going to add to that. How do we know in this equation that they're the vegetables, animals and not that we are the vegetable to them?

[Neil DeGrasse Tyson]

Exactly, exactly, yeah. So, Jill, is there sort of an ethical standards that you guys like a manifesto that's plastered up on your walls at the SETI Institute?

[Jill Tarter]

Yes. A long time ago, back in the 80s, we worked with the International Institute of Space Law to create a Declaration of Principles for Dealing with the Detection of Extraterrestrial Technologies. And one of the important bullets in that protocol is make sure you got it right. Make sure that whatever you're going to announce is not some flaw in your detection system, that it really is what you're saying it is. And that's so important that now we actually suggest that the. The most valid way of searching is to search with at least two instruments widely separated on the surface of the Earth, so that the signals received by those two instruments will have a calculable Doppler shift between signals arriving here and signals arriving there. And that is a good signature to be looking for in addition to whatever's embedded in the information content of the signal.

[Neil DeGrasse Tyson]

Right, but that's not related to the ethics of how you would treat aliens. Right, so in the code of ethics, that's good to make sure that you measure that what you say is what it is. But if we come upon aliens, is there some code of how we would treat them?

[Jill Tarter]

You're talking about ethics, and I was talking about a declaration of principles. The ethics are going to come from probably the religious entities across the planet, and those are different and they have different perspectives. Some would be threatened by this discovery because it isn't consistent with their teachings. And others would simply say, no, no. Many different life forms in the universe are just another example of gods, or let's say, God, omnipotence and power. So the ethics come not from the technologies, not from the principles that I can have anything to do with, but they're going to come from religious entities. And as long as you're talking about microbes, nobody much cares. But once you start to talk about intelligent beings, then these other codes of ethics get brought to bear. And again, as I said, they're not all going to have the same conclusions or the same desires.

[Neil DeGrasse Tyson]

That would make it very difficult given how many religions there are in the world and what they're they'd all have to agree on what a code of ethics would be. And if they're all coming from different religious traditions, that can be very hard to arrive at an agreement. And we have our first encounter, and so we have to see how that unfolds. For sure.

[Jill Tarter]

Yeah. And there's another unintended consequence that you might not think about, and that's geographical. So suppose that whatever technosignatures are detected or detectable are only detected from extremely southern locations or northern locations. Now, if it comes from the south, from the Antarctic, we already have some methods or agreements for how to share data that's collected in the Antarctic. But if you get to a point where it can only be seen from the Arctic now, you're in really hot water because so many different countries and nation states are claiming sovereignty over different pieces of the Arctic.

[Neil DeGrasse Tyson]

The Chinese have the biggest radio telescope in the world today, so it could be that the first alien contact will be with Chinese astrophysicists.

[Jill Tarter]

That's correct. And they built an amusement park right next to that telescope. Yes. I worry about the potential for creating a haves and have nots.

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[Matt Kirshen]

We got some more. So Dave McNeely from San Diego, California says, Dr. Tata, it's a huge pleasure. I met you once at the inaugural seticon in 2010 in Santa Clara. I'm studying for a master's degree in space studies and SETI is an enormous driving force in my life. My question, I'm sure you get this all the time, but considering radio technology is limited to the speed of light, doesn't it make sense that more advanced extraterrestrial intelligences would be communicating with each other using something different? Surely they are not using radio communication internally across vast interstellar distances?

[Neil DeGrasse Tyson]

Yeah. How much of the physics that we know today is limiting us on the possibility that there's new physics in the future? Yeah, I mean, again, we have the bias of our own times. All right. And we're thinking they would use radio waves moving at the speed of light. And do you guys think about possible future technologies that could be game changing on this landscape?

[Jill Tarter]

Yeah, we think about it, but we don't know how to do it right.

[Neil DeGrasse Tyson]

Okay, that's the answer. That's the simple answer. Yeah. I think in Star Trek their communication channels are on, what do they call it, Subnet? Where's Charles when you need him, our geek in chief? In Star Trek, it wouldn't be helpful to talk to Starfleet Command using radio waves limited by the speed of light, because there would not be a witty repartee between the captain and headquarters. So there's some subnet or something that apparently there's signals that can get through instantly just like a regular phone call. And so it's solved in Star Trek, which is several centuries in our future.

[Matt Kirshen]

Something to look forward to.

[Neil DeGrasse Tyson]

Yeah, definitely.

[Jill Tarter]

Right. Hey, if the Star Trek folks, the producers and creators, can tell us how to do it, then we should listen. But so far, superluminal communication is not within our reach. Superluminal simply means faster than the speed of light. And we talk about it, people write papers about it, but we don't know how to do it.

[Neil DeGrasse Tyson]

And it's a cool word anyway. That kind of means what it sounds like it says. So I like words like that. So I think, Matt, we have time for one more. A good one. You got a good one there.

[Matt Kirshen]

Okay, well, I think this is a Good. A sort of less technical but deep question. Pinky MacGyver asks, How lucky do we have to be for our ability to detect life to coincide in time with that life's ability to be detected?

[Neil DeGrasse Tyson]

Does that take us back to your glass of water in the ocean analogy?

[Jill Tarter]

That's absolutely correct, Neil. We have to be pretty lucky in order to end up being co temporal, being able to be around at the same time for both transmitter and receiver. So unless L, the factor in the Drake Equation, which says how long technological civilizations or the technology persists, unless L is large, there's not going to be any success. There won't be any overlap. But again, I'm of the opinion that I like to think about turning that around and saying that if we detect someone else's technology, it means that L has to be large and that we have a long future.

[Neil DeGrasse Tyson]

And remind us about the Drake Equation, which played a role in the movie Contact. If someone wants, like, a full celebration of the Drake Equation. But can you just remind us where that came about and what it. What it attempts to do?

[Jill Tarter]

Well, the Drake Equation is actually the agenda for a scientific meeting that Frank Drake put together at Green Bank, West Virginia, at the telescope there. And it says the number, and it's actually not an equation because it doesn't have a solution, but it's written as the form of an equation. So it says the number of technological civilizations in the Milky Way galaxy with whom we could communicate can be estimated by taking the rate of star formation in the galaxy and multiplying that by the fraction of stars that have the appropriate conditions to be suitable hosts for living planets. Multiply that by the average number of such planets around each star. Multiply that by. By the fraction of those planetary planets that develop a technology, multiplied that by the average longevity of the technologies, and you end up with an estimate of the number of communications.

[Neil DeGrasse Tyson]

Zero.

[Jill Tarter]

Can't be zero, because we're here. It doesn't say, oh, we're here.

[Neil DeGrasse Tyson]

Okay, we got to get at least one out of that region.

[Jill Tarter]

It's at least one. But unless L is large, it's a small.

[Neil DeGrasse Tyson]

Very good.

[Matt Kirshen]

So you're saying we use the length that we've existed as a civilization as our best guess for how long civilizations can run on average.

[Neil DeGrasse Tyson]

We have no other guess correct, Matt.

[Jill Tarter]

It's actually a lower limit. We know that it's possible to have a technology exist for at least as long as we have, and that's a hundred or so years, but we don't know what the upper limit is.

[Neil DeGrasse Tyson]

And that hundred years comes from the earliest radio telescope signals that we could detect that put us on the map, on the SETI map.

[Jill Tarter]

Right back to Kokone.

[Neil DeGrasse Tyson]

What are your thoughts on all of the congressional hearings regarding sightings of unidentified anomalous phenomena rebranded from UFOs? Were you tapped for your expertise in any of this and what are your reflections on it?

[Jill Tarter]

Well, first of all, I have no expertise in that and nobody came knocking on my door. But there's a gentleman by the name of Nick west who has done a lot of careful studies of some of the most touted and the most recent releases of videos from different, the Navy in particular, and has come up with. All right, if you actually analyze what you're seeing and not looking at it with a bias that what you're seeing is something having to do with an extraterrestrial spacecraft, you can come up with very plausible explanations.

[Neil DeGrasse Tyson]

So at least. So somebody is tasked themselves to just be sort of not jump to extraordinary conclusions. As you quoted Carl Sagan earlier, if you have an extraordinary claim, there should be an extraordinary evidence behind it. And if you can explain the evidence with ordinary means and ordinary physics and ordinary technologies, ordinary detector glitches, then, you know, go home.

[Jill Tarter]

Occam's razor. Yes.

[Neil DeGrasse Tyson]

Well, what we should do is if we. If aliens ever land, we should bring them to you. I think.

[Jill Tarter]

I don't know, maybe you should bring them to the cats of the world or the elephants of the world who have amazing memories and capabilities. We're just beginning to understand other species.

[Neil DeGrasse Tyson]

This topic will never go away because it has unlimited public appetite and as evidenced by every next movie that addresses that phenomenon. In fact, just now there's Alien Earth just came out, which is. That's the Alien franchise. But now the alien's no longer in space, it's on Earth. Okay.

[Matt Kirshen]

The last thing we want. Who let that happen?

[Neil DeGrasse Tyson]

Who let that. Somebody left. Left the door open. They forgot to close the door behind them. So, yeah, there's no end of this. And movies are making money hand over fist. They should. So, Jill, you should. They should have a volunteer tax that any percentage of a movie that depicts aliens should be given to seti. I think I'm going to post that on social media. That's what I'm going to do.

[Jill Tarter]

That's great, Neil. I've been making that argument for a long time and it hasn't taken hold. So maybe if.

[Neil DeGrasse Tyson]

Neil, let me see what I can do with it.

[Jill Tarter]

We'll get there.

[Neil DeGrasse Tyson]

Well, hi, Jill. It's been delight to have you back on to StarTalk. I like checking in with you on the latest developments in the SETI universe, the SETiverse. And good to hear that it's alive and well and funded, at least at levels that at least for now it's funded and. And we're also delighted to learn that when you make contact, you will tell the world you're not going to run to members of Congress and keep it in a locked box in a back room. That that's. You'll do what any scientist would do in your situation. And so we look forward to that day.

[Jill Tarter]

Me too. I look forward to that.

[Neil DeGrasse Tyson]

What was that question, Matt? Unless they think we're carrots. What was it?

[Matt Kirshen]

Yeah. Are we there animals and plants? I don't know.

[Neil DeGrasse Tyson]

Right. Yeah. Are we there? Yeah. Are we the something to be eaten? Because they're. They're long voyage. They're hungry, tasty humans.

[Matt Kirshen]

Let's hope they're fussy eaters. They don't like their broccoli.

[Jill Tarter]

They have the technology to come here and consider you as lunch. They don't need that. They can manufacture you.

[Matt Kirshen]

Oh, that's true. But you know, it might be a gourmet thing. You know, we don't need meat, but people still do. Could be a status thing.

[Neil DeGrasse Tyson]

I will die knowing I am tasty. How's that? Is that all right? We gotta call it quits there. So Jill's been delight to have you back on.

[Jill Tarter]

Oh, it's a pleasure, Neil. It's always great to talk to you.

[Neil DeGrasse Tyson]

And we'll check in with you again every now and then to make sure we don't fall too far behind on the latest SETI developments. And Matt, we can find you on mattkirshen.com you're on the road.

[Matt Kirshen]

Absolutely. I'd love to see StarTalk listeners out in my audiences. So, yeah, mattkirchen.com for all my dates. And probably science is the podcast.

[Neil DeGrasse Tyson]

So this has been another episode of StarTalk Cosmic Queries, the SETI Edition. I'm Neil Degrasse Tyson, and as always, I bid you to keep looking up. Keep listening up.

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[Greenlight Narrator]

Did you know that parents rank financial literacy as the number one most difficult life skill to teach? Meet Greenlight, the debit card and money app for families. With Greenlight, you can set up chores, automate allowance and keep an eye on your kids spending with real time notifications, kids learn to earn, save and spend wisely. And parents can rest easy knowing their kids are learning about money with guardrails in place. Sign up for Greenlight [e-mail] podcast.