Cosmic Queries: Aliens

Join us for an out-of-this-world episode of Cosmic Queries when astrophysicist Neil deGrasse Tyson provides down-to-earth answers to fan questions about aliens.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Neil deGrasse Tyson?

  Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now.

• 0:21Neil deGrasse Tyson?

  Welcome to StarTalk Radio. I'm your host Neil deGrasse Tyson, and I'm an astrophysicist at the American Museum of Natural History, right here in New York City, where I also serve as the Director of the Hayden Planetarium. You're listening to StarTalk Radio, and I've got with me, co-hosting, LeAnn Lord. LeAnn, welcome back!

• 0:42Speaker 01

  Thank you Neil!

• 0:43Neil deGrasse Tyson?

  Welcome back, LeAnn, professional comedian.

• 0:45Speaker 01

  Professional stand-up comedian.

• 0:47Neil deGrasse Tyson?

  Intrepid explorer of the world.

• 0:49Speaker 01

  World traveler, absolutely.

• 0:51Neil deGrasse Tyson?

  World traveler, every time I turn around, I follow your tweets, you're popping up in another city, making them laugh.

• 0:56Speaker 01

  That's what I do. Have laughter, we'll travel.

• 0:58Neil deGrasse Tyson?

  Not only that, you show up in the Middle East, too, with troops.

• 1:01Speaker 01

  I do, I do. I've performed in Baghdad, which is actually safer than Brooklyn.

• 1:06Neil deGrasse Tyson?

  So you and Bob Hope, right? Baghdad's safer than Brooklyn.

• 1:09Speaker 01

  Although, well, I get security there.

• 1:11Neil deGrasse Tyson?

  Not in Brooklyn, you live in Brooklyn.

• 1:13Speaker 01

  Well, I'm in Queens.

• 1:14Neil deGrasse Tyson?

  Okay.

• 1:15Speaker 01

  See, now the Brooklyn fans are gonna be so mad.

• 1:17Neil deGrasse Tyson?

  Oh, yeah. But, no, it's a great thing, you and Bob Hope, I mean, what a storied tradition of entertaining the troops.

• 1:23Speaker 01

  I love it.

• 1:24Neil deGrasse Tyson?

  So, thank you. So today, we are StarTalk After Hours. That's why, that's not the name of it, but that's how I feel when I'm doing StarTalk Cosmic Queries, where the cosmic query part of StarTalk Radio, where your questions get answered, and we solicit them in advance on Facebook, on Twitter, and you've, and LeAnn, you've got the supply, you've got the stash.

• 1:47Speaker 01

  I have got the stash of questions.

• 1:48Neil deGrasse Tyson?

  You're gonna handpick them, I've not seen them?

• 1:49Speaker 01

  No.

• 1:50Neil deGrasse Tyson?

  And, so be kind to me, as you send them my way.

• 1:53Speaker 01

  I will, I will do what I can, I make no promises.

• 1:55Neil deGrasse Tyson?

  The topic today is aliens.

• 1:57Speaker 01

  Yes. Aliens are, this is that little...

• 1:59Neil deGrasse Tyson?

  It's a huge topic.

• 2:00Speaker 01

  It is a huge topic. So I, it is, it was very difficult, but I've tried to narrow them down.

• 2:05Neil deGrasse Tyson?

  Okay.

• 2:06Speaker 01

  And we're gonna have some fun.

• 2:07Neil deGrasse Tyson?

  All right, let's do it.

• 2:08Speaker 01

  All right. This first question comes from Watson McKeel, and he wants to know, what other senses could aliens have besides the five we humans possess?

• 2:17Neil deGrasse Tyson?

  Awesome question, Watson. Is that the dude's name, Watson?

• 2:22Speaker 01

  His name is Watson.

• 2:23Neil deGrasse Tyson?

  If your name is Watson, you can only ask an awesome question.

• 2:25Speaker 01

  Oh, I know.

• 2:26Neil deGrasse Tyson?

  So, first of all... It's lately, people have imagined or considered that we have more than five senses, right? We have thing, a sense of balance, you know, a sense of.

• 2:36Speaker 01

  Some of us.

• 2:37Neil deGrasse Tyson?

  Yeah.

• 2:38Speaker 01

  Have you been to a dance club? It's awkward out there.

• 2:41Neil deGrasse Tyson?

  So, I'm, I'm gonna stick with the five, just for the purposes of this question, because they're clean and classical, and they're well-understood by us all. It turns out, that the people who would claim they might have maybe a sixth sense, where they can know something beyond what the five senses deliver, that's what science is. Science is all about, either enhancing the senses that we have.

• 3:06Speaker 01

  Okay.

• 3:07Neil deGrasse Tyson?

  Or inventing senses that our human biology never considered.

• 3:11Speaker 01

  Hmm.

• 3:12Neil deGrasse Tyson?

  That's what we are, that's what we do. So, we have, we can detect slight changes in gravitational fields, we can detect magnetic, you have no way to detect a magnetic field? You walk right on through it, and you wouldn't, your jewelry would fly in one direction or another, if it were magnetic, but your human biology could not detect whether or not you were in a magnetic field. So, we have tools that will do that. If you were exposed to high-energy radiation, you have no detectors for that. Eventually, you would know, because your body parts start falling off.

• 3:43Speaker 01

  Why's my hair falling off?

• 3:44Neil deGrasse Tyson?

  Yeah, you have cancers and things, you'd find out later, but not while it's happening.

• 3:49Speaker 01

  Right.

• 3:50Neil deGrasse Tyson?

  So, hence, we're susceptible to ionizing radiation, because you don't know it while it's happening. But we have detectors that can do this. We can detect ultraviolet light, outside the visible range of the human eye. The retina cannot see ultraviolet, can't see infrared, can't see microwaves. We harness these, we observe these in the universe, we use them all around us. Your cellphone uses microwaves. It is a detector of things your human biology cannot see, wouldn't even know is there. So, when you wanna ask, what senses might an alien have? We have a, we have a whole repository of things they might be able to see, detect, think up, notice, that our human biology can't, but our science can.

• 4:34Neil deGrasse Tyson?

  So I'd reach into that bag of detectors and say, "Alien, what do you got that we don't got?" All right? And maybe they can detect radio waves. Maybe they can see microwaves with their eyes. Maybe they can know when they're about to be rendered sterile by being exposed to high-energy radiation. Maybe they can figure all this out and know what beams to step into and what not. What stars to set up their civilization around and what not. Some stars are very dangerous to live around, but you only know after you catch organ diseases and die. So...

• 5:13Speaker 01

  I have to say, I'm sitting here quiet for two reasons. One, I'm mesmerized, and two, I'm feeling very inadequate as a human being with my little limited five senses.

• 5:23Neil deGrasse Tyson?

  Oh, yeah, yeah. You should so... That is, that's how you should feel.

• 5:26Speaker 01

  Okay.

• 5:27Neil deGrasse Tyson?

  Yeah, just feel like they're not only incomplete, they also do not serve you well. They don't serve you accurately. And this was the delay that science experienced. Science was not invented until like the 1600s, as we now practice it. And until then, people say, "I got my senses. Seeing is believing." Well, no, no. Seeing is what you think is true, what you want to be there. Seeing is one of the most susceptible of our senses in terms of what's...

• 5:59Speaker 01

  Well, thank goodness. That's how the species continues.

• 6:02Neil deGrasse Tyson?

  Exactly.

• 6:03Speaker 01

  Thank goodness for our eyes deceiving us, or some of us wouldn't be here.

• 6:08Neil deGrasse Tyson?

  What, there's a country western song, "The girls get prettier at closing time at the bar."

• 6:14Speaker 01

  That sounds about right.

• 6:15Neil deGrasse Tyson?

  Yeah, so our senses are susceptible to all manner of distortion. And so it wasn't until science was invented that we made any meaningful headway in our understanding of the physical universe. So I'd certainly give aliens the opportunity to have many of our scientific senses as part of their own alien biology.

• 6:35Speaker 01

  Wow, that's cool.

• 6:37Neil deGrasse Tyson?

  Sorry, that was a really long answer. Is that all those okay?

• 6:39Speaker 01

  I am very cool with that. I think Watson is going to be very happy.

• 6:44Neil deGrasse Tyson?

  And you know, we want all aliens to be, we expect them all to be able to read our minds.

• 6:48Speaker 01

  Yeah.

• 6:49Neil deGrasse Tyson?

  Yeah, but of course, they'd have to know English, you know?

• 6:52Speaker 01

  Well, if they're here in America, depending on where they are on the planet.

• 6:55Neil deGrasse Tyson?

  Oh, of course, they have to read Serbian or something.

• 6:58Speaker 01

  Yeah, there's lots of languages.

• 7:00Neil deGrasse Tyson?

  They would need a language translator. So that'd be cool.

• 7:03Speaker 01

  Well, now, if I'm putting on my Neil deGrasse Tyson hat, if they can actually read our minds, perhaps they're reading biochemical signatures independent of language.

• 7:11Neil deGrasse Tyson?

  Ooh. She suits, she scores. Oh, my gosh.

• 7:17Speaker 01

  I should hang out here more often.

• 7:18Neil deGrasse Tyson?

  So what you're saying is the language is just a layer on top of the thoughts that lay beneath them.

• 7:24Speaker 01

  Yes.

• 7:25Neil deGrasse Tyson?

  And those thoughts are propagated, stimulated by biochemical reactions across the synapses of the human mind.

• 7:32Speaker 01

  Yeah, that's what I'm thinking, saying. Exactly. You're reading my mind, alien Doctor Tyson.

• 7:38Neil deGrasse Tyson?

  We gotta wind down this first segment of StarTalk after hours. StarTalk: The Cosmic Queries. And Leanne, thanks for being here for this. Several segments to come for you just bringing questions from the internet.

• 7:51Speaker 01

  Bringing it from the internet.

• 7:52Neil deGrasse Tyson?

  Landing right here in the lap of StarTalk Radio. We'll see you in a minute.

• 8:14Neil deGrasse Tyson?

  We're back on StarTalk: The Cosmic Queries Hour. I've got Leanne Lord. Leanne?

• 8:19Speaker 01

  Yes.

• 8:20Neil deGrasse Tyson?

  You don't spell your name like a normal person.

• 8:22Speaker 01

  I don't really know what "normal" means.

• 8:24Neil deGrasse Tyson?

  Well, I wouldn't care how you name spell, but I have to figure out how to spell it to follow you on Twitter.

• 8:27Speaker 01

  That's true. It does take a little bit of an extra step.

• 8:30Neil deGrasse Tyson?

  An extra step. L-E-I-G-H-A-N-N.

• 8:33Speaker 01

  Right. Thank you, Mom and Dad.

• 8:35Neil deGrasse Tyson?

  Leanne Lord, one word at Twitter.

• 8:37Speaker 01

  Leanne Lord, mm-hmm, all together, all at Twitter.

• 8:40Neil deGrasse Tyson?

  Excellent, excellent. You're listening to StarTalk Radio. You know, we're on the web, startalkradio.net. We also tweet @StarTalkRadio. Good guess if you figured that out. And of course, we're on Facebook. You can like us there. Find us @StarTalkRadio.

• 8:57Neil deGrasse Tyson?

  And in fact, these are the places where we have collected these questions.

• 9:00Speaker 01

  Yes.

• 9:01Neil deGrasse Tyson?

  For our Cosmic Queries Hour. And these questions are all about aliens.

• 9:05Speaker 01

  Yes.

• 9:05Neil deGrasse Tyson?

  Okay, who's, what do you got next?

• 9:07Speaker 01

  Well, I have a question about aliens from Robert Gilman.

• 9:10Neil deGrasse Tyson?

  Mm-hmm.

• 9:10Speaker 01

  And, uh...

• 9:11Neil deGrasse Tyson?

  Do they ever say where they're from?

• 9:12Speaker 01

  No, I don't.

• 9:13Neil deGrasse Tyson?

  Okay, we gotta get them. I'd like knowing where they're from.

• 9:15Speaker 01

  Yeah, that would be nice. That would be nice. Um, this is a, I believe, a multi-part question, so I will try my best, Robert. Uh, forgive me if I stumble.

• 9:22Neil deGrasse Tyson?

  And by the way, if I don't know the answer, I'll say, "Next."

• 9:24Speaker 01

  Okay, no, no, no. So I'll go through this seventeen-page question, and you'll just say, "Next."

• 9:28Neil deGrasse Tyson?

  Or, or if I am not authorized to answer a question, I'll say, "Next."

• 9:33Speaker 01

  Right, right. We might not have the security clearance to hear the answer. Got it.

• 9:37Neil deGrasse Tyson?

  All right.

• 9:37Speaker 01

  All right.

• 9:38Neil deGrasse Tyson?

  Ready for you.

• 9:38Speaker 01

  All right. "Is there any law, theory, or speculation that dictates the bounds of physical characteristics of life forms? For example, would all life forms throughout the universe give an adequate evolutionary time eventually resemble the rough size of terrestrial animals? Would the gravitational effect of the planet influence the size of the inhabitants?"

• 9:58Neil deGrasse Tyson?

  This is an awesome ques- this is like an intelligent ques-

• 10:01Speaker 01

  Yeah, these are great!

• 10:02Neil deGrasse Tyson?

  These are awesome!

• 10:03Speaker 01

  Yeah, I love it.

• 10:04Neil deGrasse Tyson?

  Man!

• 10:04Speaker 01

  I promise I'll find something less intelligent.

• 10:06Neil deGrasse Tyson?

  I just, I just wanna celebrate the awesomosity of that question.

• 10:10Speaker 01

  You are awesome, Robert. Did you hear that?

• 10:11Neil deGrasse Tyson?

  So, uh, Robert is, is correct. There are laws of physics that limit what biology can be.

• 10:19Speaker 01

  Okay.

• 10:19Neil deGrasse Tyson?

  So a couple of things. For example, if you're really, really big, could you have life forms the size of an entire galaxy, let's say? I mean, just imagine. Just, let's go, let's go extreme on this.

• 10:31Speaker 01

  Okay, a thought experiment.

• 10:32Neil deGrasse Tyson?

  All right, thought experiment. All right, all right, all right, how about the size of the solar system? You're some space giant. And you wanna be the size of the solar system. All right. Well...

• 10:42Speaker 01

  I would think a diet is in order immediately.

• 10:45Neil deGrasse Tyson?

  Well, here's the problem. Suppose something happens to one part of your body, and you're gonna react to that. Someone tickles your toe. But you're the size of the solar system. Well, the signal cannot get to your brain any faster than the speed of light. And so if you want to cross the solar system, it's like five hours across, hours across. Okay, I tickle your toe, several hours later, your brain learns of it. And then you say, oh, go scratch your toe. Cause you have an itch down there and two several hours later goes by and so five, eight, nine, 10 hours later, you scratch your toe. But by then it's too late. If harm is being done to you, you cannot react in a sensible timeframe.

• 11:27Neil deGrasse Tyson?

  So survival kind of depends on the ability of the organism to function as a coherent responsive entity in reaction to stress in its environment. So there's a size above which I don't think it's likely you're gonna find life.

• 11:45Speaker 01

  So would that go any ways to explaining why short people are more reactive perhaps than bigger people? Because they're more compact and they have more of a trigger to that reaction. I'm trying to interpret.

• 12:00Neil deGrasse Tyson?

  I didn't know short people were more reactive.

• 12:02Speaker 01

  Well, the Napoleon complex perhaps?

• 12:04Neil deGrasse Tyson?

  Okay, oh, I see. They react to, yeah, and they can be a little spunkier.

• 12:07Speaker 01

  Just a bit.

• 12:08Neil deGrasse Tyson?

  There are no big spunky people, have you noticed?

• 12:10Speaker 01

  I've noticed that. I've noticed that. It's always the little dogs that start stuff with the dog.

• 12:14Neil deGrasse Tyson?

  Yeah, yeah, the big ones like I'm tired, I'm too tired.

• 12:16Speaker 01

  Exactly. The Saint Bernard's just trying to chill.

• 12:18Neil deGrasse Tyson?

  I'm just trying, yeah, yeah.

• 12:19Speaker 01

  And the Chihuahua is just hanging on.

• 12:21Neil deGrasse Tyson?

  No hyper Saint Bernards, right? So maybe we get a little bit of that fact, a little bit of that revealed. Uh, in this other things, there's a size smaller than which you cannot realistically be, given the laws of quantum physics. There's a size below which quantum fluctuations, these are the, the vibration of particles on the smallest scale, prevents anything from happening in any coherent way. You can't have circulatory systems, you can't have anything that has predictable behavior because in that realm, nothing is predictable with any accuracy. So, sorry, you can predict statistically, but you can't say exactly what a particle is going to do, when it's gonna do it. And life, I don't think. Thrives under those conditions.

• 13:06Neil deGrasse Tyson?

  So you can't, life can't be too big, it can't be too small. Also, it needs an energy source. So you gotta have some sort, you can't just be out there in the middle of nowhere and, and survive.

• 13:15Speaker 01

  Okay.

• 13:16Neil deGrasse Tyson?

  And so we think these are fundamental to life. I'm betting you that the life will be based chemically on carbon. Cause carbon is the most chemically fertile element on the entire periodic table. If you're gonna have life based on some element, base it on the one that makes the most kinda elements in the most kinda ways. And that would be carbon.

• 13:35Speaker 01

  Okay.

• 13:36Neil deGrasse Tyson?

  And carbon is bountiful in the universe. And I, I, we had, uh, Jon Stewart as one of our guests on StarTalk. And did you know he majored in chemistry when he started college?

• 13:45Speaker 01

  I did not.

• 13:47Neil deGrasse Tyson?

  To, to psychology. And I said, well, oh, so I had the geek question, do you have a favorite element? He said, yes, carbon. I said, yeah, yes. I said, but I wanted to hear why it was his favorite element. I said, why? He said, because it was the slut of the periodic table. It made molecules in every which way you can. So I bet you that life in the universe is also based on carbon. By the sheer abundance of it and by how sticky it is in its capacity to make complex molecules.

• 14:16Speaker 01

  Hmm. Well, you know what? That actually brings up, um, a question I was looking here, cause someone had asked this and, uh, had asked, what is, what would a silicon-based life form look like?

• 14:26Neil deGrasse Tyson?

  Yeah, so, you know, you know, the reason why people suggest silicon right after carbon?

• 14:29Speaker 01

  Why?

• 14:30Neil deGrasse Tyson?

  Because, in case you didn't know, you must not remember that chart of mysterious boxes that hang before you for an entire school year in your chemistry class.

• 14:40Speaker 01

  I do, I, I remember the, I had therapy that year.

• 14:44Neil deGrasse Tyson?

  Okay.

• 14:44Speaker 01

  It was, it was rough. There was a chart and I cried a lot.

• 14:47Neil deGrasse Tyson?

  All right. And it's called the periodic table of elements because certain features of the elements repeat themselves as you go left to right across the table. So that's why it's called periodic, all right? And so if you look at the element that sits right below carbon. Do you have your pocket periodic table? You looking it up now?

• 15:05Speaker 01

  Oh, absolutely. There's an app for that.

• 15:07Neil deGrasse Tyson?

  Right, there's an app for this. So, an app for looking up the periodic table. And elements in a column bond with the same other elements that are out there in the universe. This is part of the repeating behavior as you cycle through the chart. So, carbon has six atoms in its outer shell. I'm sorry, it has six electrons in its outer shell, okay? And so it can combine with other atoms that have electrons that can join it in its shell, or it can donate electrons to other atoms. They can combine in so many different ways.

• 15:41Speaker 01

  Lending to the slut reputation.

• 15:44Neil deGrasse Tyson?

  Lending to the slut reputation. Directly below carbon is silicon.

• 15:50Speaker 01

  Oh, it's all coming back to me now.

• 15:51Neil deGrasse Tyson?

  Yes, not silicone, that's different.

• 15:53Speaker 01

  That's inexpensive.

• 15:55Neil deGrasse Tyson?

  Right, that's a different procedure.

• 15:57Speaker 01

  Did I overshare?

• 16:00Neil deGrasse Tyson?

  TMI?

• 16:01Speaker 01

  TMI, everybody. Forget you heard that.

• 16:03Neil deGrasse Tyson?

  Alright, so silicon as an element combines in similar ways as does carbon. It's just less abundant in the universe, and its bonds tend to be very strong. Like, one of the active ingredients in rock is silicon. And so, you don't want the bond to be too strong, because then it's harder to experiment. Life is this big experiment in chemistry. And if you make a bond that lasts a billion years, you're not...

• 16:29Speaker 01

  Not a lot of experimentation.

• 16:31Neil deGrasse Tyson?

  Yeah, rocks are rocks, right? I mean, they're different kinds, but they're not getting up and walking around. And so, chemicals based on carbon have the capacity to offer extraordinary diversity in their chemical offerings.

• 16:45Speaker 01

  And thus more flexible? Can you use the word flexibility in what it can do?

• 16:50Neil deGrasse Tyson?

  Oh, yes, yes. In fact, I said carbon has six atoms. No, it has four. The point is, it can receive electrons in its outer shell. It can donate electrons in many different ways. And so, carbon has four electrons in its outer shell.

• 17:04Speaker 01

  Alrighty. Oh, well, now this one, these questions seem to flow. I love this. "Do you think it's possible that there could be extraterrestrial life that does not take a solid form?" Um, let's see, I know we're mostly liquid, but our bodies act as solids. And I like this question because I think I saw this on Doctor Who.

• 17:24Neil deGrasse Tyson?

  Oh, you're a Whovian.

• 17:26Speaker 01

  I, I am now.

• 17:27Neil deGrasse Tyson?

  Oh, yeah, yeah. Once you get hooked, there's no going back.

• 17:29Speaker 01

  No, not at all. Not at all.

• 17:30Neil deGrasse Tyson?

  And then you watch that instead of other shows you thought you liked.

• 17:33Speaker 01

  Right.

• 17:33Neil deGrasse Tyson?

  Right, right. It supplants the, um, so, so I don't see why not. I mean, no one ever accused an amoeba of being solid. So we've got non-solid creatures here on Earth. So...

• 17:45Speaker 01

  So undependable.

• 17:46Neil deGrasse Tyson?

  So surely aliens would come up with some amoeba-like creatures. And plus, you have to like the Blob from that original Stephen McQueen movie in 1958. That was a non-solid alien form that I thought was quite creative because it didn't look like a, an actor in a costume. And so an amoeba, a huge, human-sized amoeba would be just totally terrifying and awesome. And so I don't see why. Whether you can have gaseous forms of life, that's a little more questionable as far as I can tell. We're going to come back to StarTalk, the Cosmic Queries Hour. We'll be right back.

• 18:39Neil deGrasse Tyson?

  We're back with StarTalk Radio. I'm Neil deGrasse Tyson, your host. I'm an astrophysicist and serving as your talk show host. Yes, and I have Leanne Lord right here in studio with me, comedienne Leanne Lord.

• 18:53Speaker 01

  Yes, live in captivity.

• 18:55Neil deGrasse Tyson?

  Live in captivity. We captured her for this Cosmic Queries Hour where you send in your questions about the shows that we do. And this one is on cosmic aliens.

• 19:06Speaker 01

  Yes.

• 19:06Neil deGrasse Tyson?

  Yeah, so, not illegal aliens, but cosmic aliens, right?

• 19:09Speaker 01

  [laughing]

• 19:10Neil deGrasse Tyson?

  So, so what do you got for me? Yeah, I haven't seen these questions. You're just plucking them from the repository?

• 19:17Speaker 01

  Yes.

• 19:17Neil deGrasse Tyson?

  All right, what do you got?

• 19:18Speaker 01

  Okay, this next question is from Colin Walker and, uh...

• 19:22Neil deGrasse Tyson?

  That sounds so proper.

• 19:23Speaker 01

  Colin Walker.

• 19:24Neil deGrasse Tyson?

  Sounds very British.

• 19:25Speaker 01

  I probably should have said it's from Colin Walker. And it wants to know, what about the WOW signal? Let's delve into that mystery. And I have to say, that is a mystery to me because I don't know what WOW, W-O-W, I'm, I'm, I mean, that's Whip 'Em Out Wednesdays?

• 19:39Neil deGrasse Tyson?

  Oh, yeah. You know, I, I once knew all about the WOW signal and there was a, I think that was a radio... I'd have to go back and do my homework on that. I'd have to go back and do my homework on that. There were the radio telescopes. If I the little bit that I remember, I've long since forgotten it, was that there was a signal detected by radio telescopes that was not of known terrestrial origin or even of of cosmic origin that from objects whose signatures we already know and understand. So it was then identified on a on a chart. But the concern was, could that have been a signal sent to us by aliens? By intelligent aliens, a radio signal?

• 20:22Speaker 01

  Um, well, perhaps I'm combining ideas that don't belong, but it was that the basis of Carl Sagan's Contact?

• 20:29Neil deGrasse Tyson?

  Oh, no, no, no.

• 20:30Speaker 01

  Something completely different.

• 20:31Neil deGrasse Tyson?

  We've been dreaming up aliens contacting us forever. Ever since there've been radio waves. And ever since we knew that radio waves can pass through the depths of space with little hindrance from intervening gas clouds that would otherwise block visible light. Right? Because you might say, why don't they just flash Morse code at us or something? And it would get blocked by all manner of dust and gas within the galaxy. So you'd send radio waves passes right through it. And so radio waves have that feature. It's very good about them. That's radio waves pass through this building so that you can get radio reception inside of buildings.

• 21:03Speaker 01

  Well, clearly where I live, I have a radio blocker. Because there are certain stations I'm just not getting.

• 21:09Neil deGrasse Tyson?

  Stations don't come in. Well, they they're blocking you. Yes, that's right.

• 21:12Speaker 01

  Yeah, I'm taking it extremely personally.

• 21:14Neil deGrasse Tyson?

  Um, so that's so the point is you can have anomalous radio signals. But you can't do anything with them unless they repeat. You see, because we're, you know, I mean, maybe it was an alien saying, hi. Well, okay, can I get some more communication, please? I need a little more than that. You know, give me digits of pi. Tell me, you know, tell me how what you had for breakfast.

• 21:42Speaker 01

  We need a conversation.

• 21:43Neil deGrasse Tyson?

  Give me a give me some more, give me more than just the one blurt of radio signal.

• 21:50Speaker 01

  That's why it's easier to talk to an adult than a child. Because a toddler will just go, hi, and move on.

• 21:56Neil deGrasse Tyson?

  So I'm, uh, so with, with, so yes, and, and by the way, some radio signals could be just a glitch in the, in the electrical current that's driving the detector. So that's why to be safe, to be secure in our interpretation, we kinda require, the, I mean, we didn't send the memo to them, but the aliens should know because we require that if you're gonna send us a signal, you wanna repeat it.

• 22:22Speaker 01

  They should know.

• 22:23Neil deGrasse Tyson?

  Because when-

• 22:23Speaker 01

  That we require.

• 22:24Neil deGrasse Tyson?

  They should.

• 22:25Speaker 01

  I'm hearing a lot of assumptions here, sir.

• 22:27Neil deGrasse Tyson?

  No, because if we-

• 22:28Speaker 01

  This is sort of how, why men and women can't communicate well.

• 22:31Neil deGrasse Tyson?

  I'm just saying.

• 22:32Speaker 01

  Women are thinking, men should know.

• 22:33Neil deGrasse Tyson?

  Uh, that's just, no.

• 22:35Speaker 01

  This is what we require.

• 22:36Neil deGrasse Tyson?

  Cause maybe we weren't listening at that instant that you sent the signal.

• 22:39Speaker 01

  Maybe.

• 22:39Neil deGrasse Tyson?

  Maybe I just turned the telescope to you now. So you should put it on a repeat loop.

• 22:44Speaker 01

  Okay.

• 22:45Neil deGrasse Tyson?

  Okay?

• 22:46Speaker 01

  If the aliens are listening, repeat loop.

• 22:48Neil deGrasse Tyson?

  On a repeat. As StarTalk after hours goes out to the universe.

• 22:54Speaker 01

  Well, they are fans.

• 22:55Neil deGrasse Tyson?

  Let the aliens know.

• 22:56Speaker 01

  Judging by some of these questions.

• 22:57Neil deGrasse Tyson?

  If you're gonna send us a signal, repeat it.

• 22:59Speaker 01

  Yes.

• 22:59Neil deGrasse Tyson?

  Uh, you know, lather, rinse, repeat until further notice.

• 23:02Speaker 01

  (laughing)

• 23:03Neil deGrasse Tyson?

  So that we can get back to you on that. So the wow signal was a singular, a singular signal in a, in a radio transmitter's detector, uh, radio receivers detector.

• 23:13Speaker 01

  So given what, everything you've said, we probably shouldn't be obsessing over this.

• 23:17Neil deGrasse Tyson?

  No, you shouldn't. And if it was aliens, there was not, nothing we can do about it. I mean, yeah.

• 23:21Speaker 01

  Okay.

• 23:21Neil deGrasse Tyson?

  Yeah.

• 23:22Speaker 01

  Moving on.

• 23:22Neil deGrasse Tyson?

  Moving on.

• 23:23Speaker 01

  Uh, the next question is from Tom Lee Cole.

• 23:25Neil deGrasse Tyson?

  Oh, by the way, and if I'm completely wrong and misremembered the whole thing, then never mind.

• 23:30Speaker 01

  I love that disclaimer. Who did that on Saturday Night Live? Who was that character?

• 23:36Neil deGrasse Tyson?

  Oh, never mind. No, that was, uh, Emily Lettella.

• 23:38Speaker 01

  Was it?

• 23:39Neil deGrasse Tyson?

  Yeah. Never mind.

• 23:40Speaker 01

  Never mind.

• 23:40Neil deGrasse Tyson?

  Yeah, the first, that you're dating yourself right there.

• 23:43Speaker 01

  Uh, dude, this Wikipedia, there's, there's Google, there's YouTube.

• 23:46Neil deGrasse Tyson?

  That's how you know about the early seasons of Saturday Night Live.

• 23:49Speaker 01

  Okay, am I not supposed to know about Beethoven? I mean, come on.

• 23:51Neil deGrasse Tyson?

  Oh, yeah, you got out of that one.

• 23:53Speaker 01

  Thank you very much. Moving on.

• 23:55Neil deGrasse Tyson?

  What else you got?

• 23:56Speaker 01

  Next question is from Tom Lee Combe.

• 23:59Neil deGrasse Tyson?

  What's the first name?

• 24:00Speaker 01

  Tom Lee.

• 24:01Neil deGrasse Tyson?

  Tom Lee.

• 24:01Speaker 01

  That's T O M L Y.

• 24:03Neil deGrasse Tyson?

  Tom Lee. Cool, okay.

• 24:05Speaker 01

  And, uh, Tom Lee wants to know how far away would an alien planet have to be from us to notice our life signatures? What would be the distance that they could figure out there's life here? I'm thinking they could smell us, depending on how good their noses were.

• 24:19Neil deGrasse Tyson?

  Uh, yeah, except, yeah, except the, the molecules that contain that which has a smell.

• 24:24Speaker 01

  Right.

• 24:25Neil deGrasse Tyson?

  Don't leave our atmosphere. And so it would have to like somehow on its own, say, I'm leaving and then wander through the universe like Rafiki smelling, uh, smelling, uh, what's the dude?

• 24:39Speaker 01

  I don't know. I don't have kids. Rafiki.

• 24:42Neil deGrasse Tyson?

  Rafiki from Lion King smelling, uh, Simba. Okay, Simba was alive and he smelled him. We gotta take a break, but I want to get back to that answer. You're listening to StarTalk, the Cosmic Query.

• 25:11Neil deGrasse Tyson?

  This is StarTalk Radio. We're back. I'm Neil deGrasse Tyson, your host, and I'm joined by my co-host, Leanne Lord. Leanne, welcome.

• 25:19Speaker 01

  Thank you.

• 25:19Neil deGrasse Tyson?

  Always good to have you here.

• 25:21Speaker 01

  Thank you.

• 25:21Neil deGrasse Tyson?

  And this is the Cosmic Queries part of StarTalk. And before the break, I only partially answered one of the questions. What was that question?

• 25:28Speaker 01

  Well, you, you were.

• 25:28Neil deGrasse Tyson?

  By Tom Lee asked us.

• 25:29Speaker 01

  Yes.

• 25:30Neil deGrasse Tyson?

  Someone named Tom Lee.

• 25:30Speaker 01

  You're actually correcting my ignorance on, uh, why the aliens cannot smell us.

• 25:34Neil deGrasse Tyson?

  Oh, yeah, they could.

• 25:34Speaker 01

  Why there's a barrier there.

• 25:36Neil deGrasse Tyson?

  Oh, the question was how far away can an alien planet detect us?

• 25:39Speaker 01

  Right, right. How, yeah, what's the, uh, what, what distance?

• 25:42Neil deGrasse Tyson?

  Yeah. And, and you said maybe they can smell us.

• 25:45Speaker 01

  Maybe they could smell us, revealing that I was an English major.

• 25:48Neil deGrasse Tyson?

  I said, no, because you're, what, the act of smelling is the intersection of molecules with your olfactory glands, olfactory senses and, and that, those molecules that carry your smell, your aroma.

• 26:01Speaker 01

  Oh, thank you.

• 26:01Neil deGrasse Tyson?

  Yes.

• 26:02Speaker 01

  I have an aroma.

• 26:03Neil deGrasse Tyson?

  It's better than saying you have a smell.

• 26:05Speaker 01

  Yes, it is.

• 26:05Neil deGrasse Tyson?

  Right. Yeah, football players smell, right? So they would have to travel through space, land on that planet, and then they'd have to pick it up. And I, and I was showing my cultural breadth by saying Rafiki in The Lion King smelled Simba, confirming that Simba was still alive when everyone thought he was dead. I'm impressed, sir. Get with the Disney program here. I'm so sorry. All right. So if they were intelligent species and they're looking for intelligence, then... They're not coming here? That's for sure, but what they can look for is the leading edge of our radio signals. And we discovered radio waves in the late 1800s. That's what led to early telegraph communication. But then, we figured out we can broadcast a signal that contains information.

• 26:50Neil deGrasse Tyson?

  And when we started broadcasting, the signal left Earth and created what we now call our radio bubble, the leading edge of the earliest radio communications of the intelligent species that lives on Earth called humans. So that radio bubble is about 70 to 80 light-years in radius out away from the Earth. So that has washed over many stars and exoplanets that we've now discovered. So if they have a good enough detector, they'd be able to interpret and a way to interpret the signal they receive, they might be, the carrier waves on the television signals, they might be able to interpret, for example, early episodes of I Love Lucy, or The Honeymooners. Lucky ducks.

• 27:35Neil deGrasse Tyson?

  Or, I just worry that they would learn how humans interact by watching those two shows. And that would be a disaster for any understanding they have of our species. So that's what they want to find intelligence. But if they wanted to find life at all, you could be much farther away than that and just look at the atmosphere and analyze the chemistry of Earth's atmosphere. And you know what they would find? They'd find oxygen. Do you know, if you took away all life from Earth, the oxygen would go away. Not at the snap of a finger, but it would go away relatively rapidly because it's life that sustains the oxygen on Earth. Oxygen, you'd never find it just hanging out, minding its own business. Because it is chemically reactive. So it's codependent.

• 28:17Neil deGrasse Tyson?

  Code codependent, I like that. And methane is another gas that is a common product of the actions of life, life as we know it. Okay. So if they knew this, they would look to Earth, look at our atmosphere, let a beam of sunlight come through it, and that sunlight... would reveal the chemistry of our atmosphere. And that's what we are doing with alien planets ourselves.

• 28:40Speaker 01

  We're looking for oxygen and methane.

• 28:41Neil deGrasse Tyson?

  Yes, and methane could tell you that there are farm animals because that's the major ingredient in cow flatulence. One, another, you know, another thing you can look for?

• 28:49Speaker 01

  Star Talk After Dog is taking an interesting turn here.

• 28:53Neil deGrasse Tyson?

  Another thing they they could look for, if they're looking at us and they say, wait a minute, they find like chlorofluorocarbons in the atmosphere, they find smog and and other pollutants, that would be the surest sign to them that there is no sign of intelligent life on Earth.

• 29:10Speaker 01

  We're here, which is not that bright.

• 29:12Neil deGrasse Tyson?

  Right, we're not that bright.

• 29:14Speaker 01

  Can I ask you?

• 29:15Neil deGrasse Tyson?

  Oh, by the way, there's a recent paper, sorry, there's a recent paper that said, if the planet has a moon and the moon comes around the backside where it's dark on the host planet, if that planet has artificially created light, that light would reflect off of their moon and you'd be able to see the nightlights reflected off the moon that orbits the planet. There's a recent research paper on possibly detecting the nighttime illumination of alien cities.

• 29:44Speaker 01

  Wow, so yet another thing we could look for.

• 29:46Neil deGrasse Tyson?

  So you could do that from, you know, a hundred, couple hundred light years away, very sensitive spectroscopic detection.

• 29:52Speaker 01

  I have a question about the bubble. The radio bubble, is that, is that a constant or is it expanding? Like, because you said, you gave a number like sixty or seventy?

• 30:00Neil deGrasse Tyson?

  Yeah, it's like seventy-five light years in radius. And it's moving at one light year distance per year because it's moving at the speed of light. And radio waves, I didn't make that clear, radio waves is a form of light.

• 30:14Speaker 01

  Okay.

• 30:14Neil deGrasse Tyson?

  All light, radio waves, gamma rays, X-rays, it's all light, including Roy G. Biv, red, orange, yellow, green, blue, indigo, violet.

• 30:21Speaker 01

  Which is how I set up my closet. Wow.

• 30:24Neil deGrasse Tyson?

  Is that right?

• 30:24Speaker 01

  I really do.

• 30:25Neil deGrasse Tyson?

  That is so awesomely geeky. Oh, my God, take a photo and we'll post it.

• 30:30Speaker 01

  I will, I will.

• 30:32Neil deGrasse Tyson?

  All right, well, we we finished that segment, we'll come back to more cosmic queries on aliens in the cosmos.

• 30:57Neil deGrasse Tyson?

  Startalk Radio, we're back. I'm Neil deGrasse Tyson with my co-host for this episode, Leanne Lord. Leanne!

• 31:03Speaker 01

  Hey Neil!

• 31:04Neil deGrasse Tyson?

  I love your word of the day and your tweets.

• 31:05Speaker 01

  Thank you so much!

• 31:07Neil deGrasse Tyson?

  And I learned something and I smile.

• 31:09Speaker 01

  That's the whole point.

• 31:10Neil deGrasse Tyson?

  Excellent. Comedian with a pedagogical mission statement.

• 31:16Speaker 01

  You feel smarter and happier at the same time. That's my goal.

• 31:20Neil deGrasse Tyson?

  There you go. This is Startalk after hours, I think of it. And we are, it's Cosmic Queries. We're reading your questions. It's kind of our give back to you. And so, Leanne, you've got, I haven't read these, so you're plucking them from our bin?

• 31:34Speaker 01

  Yes.

• 31:35Neil deGrasse Tyson?

  What have you got? These are from Facebook, I think.

• 31:36Speaker 01

  Yes, these are from Facebook. And I am very impressed with what folks are sending in. And this is from Leah Mangue, I believe that's pronounced. And she says, "My son, who's nine, wanted to know..."

• 31:47Neil deGrasse Tyson?

  Great age, by the way.

• 31:48Speaker 01

  Isn't it? I remember nine. "If you can meet an intelligent alien life form, what would your dream meeting be like? And what would you want to learn from he, she, them?"

• 31:59Neil deGrasse Tyson?

  It.

• 32:00Speaker 01

  It, yes. Covering the gamut.

• 32:03Neil deGrasse Tyson?

  That would be the most awesome encounter ever in my life.

• 32:07Speaker 01

  Very YouTubable.

• 32:08Neil deGrasse Tyson?

  Oh, yeah. So first, we have to figure out how to communicate with one another. All right? Let's assume that they're not, we can't read minds. I certainly can't read its mind. Plus, you know, you first meet them, do you extend your hand? In their culture, that could be a sign of danger, or that you want aggression.

• 32:26Speaker 01

  Aggression, war, yeah.

• 32:27Neil deGrasse Tyson?

  Right. And if they extend something of theirs, who knows what they're trying to do to you?

• 32:31Speaker 01

  Right, yeah. Mama said, "Don't touch that."

• 32:34Neil deGrasse Tyson?

  Don't touch that! So, you gotta figure the social mores and the cultural expectations of an alien who arrives. It's hard enough with interhuman alien visits, right? I mean, think about it. You know, some countries, you're not supposed to put your feet on the table. You can't say it one way, you walk another way. And that's just with our own species. Now imagine another life form that has no DNA in common with any life on Earth. So, getting, let's assume we got past that. And the alien is in a tuxedo at the dinner table.

• 33:05Speaker 01

  I love it. We're at a dinner party.

• 33:07Neil deGrasse Tyson?

  We're at a dinner party. And let's imagine I can actually have a conversation with the alien. I would want to know... First, are there as many kooky people on that alien planet as they are here?

• 33:19Speaker 01

  What do you do with your kooky people?

• 33:21Neil deGrasse Tyson?

  Yeah, when your kooky people said, "The world is gonna end this year," what do you do with them?

• 33:26Speaker 01

  We give them a reality TV show, next?

• 33:29Neil deGrasse Tyson?

  So first, I wanna get that out of the way. And then I was gonna say, you know, it took us a long time to discover science as a way of understanding the world. Was science natural to them? They had to have known science because they presumably got here on a spaceship made of some technology. So I would, I would, I'm a scientist, so I'd be curious how they came to discover what they know about the universe. And then I put forth our periodic table of elements. And I'd show them E equals mc squared. And I'd show their proudest moments. And then if they're really, really smart, they'd say, "Oh, our toddlers did that."

• 34:01Speaker 01

  Yes.

• 34:02Neil deGrasse Tyson?

  And then they'd show me something that would can be completely beyond. But I'd say, "Wait a minute." And I'd roll up Stephen Hawking and I'd say, "Steve, what do you make of this?" He might not know either. So it could be that he's so much smarter than us that we couldn't even have a conversation. I mean, imagine, imagine chimpanzees discovering humans and wanting to invite us to their dinner table. What would we talk about with them? We could say, "Hey, how do you feel today?" And they wouldn't be able to decode what we said. They couldn't speak with us. They, you know, they'd ask us, "Did our termites taste good today?" And that would be it, right? So I don't know that we'd even be on the same level. If they had enough technology to get here, they're gonna be ahead of us. And maybe their simplest thoughts transcend even the most complex imaginings of our species.

• 34:47Speaker 01

  I, I believe I saw this on an episode of Stargate, SG-1.

• 34:51Neil deGrasse Tyson?

  SG-1, yeah.

• 34:52Speaker 01

  There is some incompatibility there.

• 34:53Neil deGrasse Tyson?

  There could be some intellectual incompatibility, unresolvable. But if we're on the same level, I just compare what science discoveries have made. And then I turn to art and I say, "Do you guys, what do you guys do to, to stimulate the senses that you have to take in the world around you?" Because our five senses, we invest a lot of emotional, intellectual, and financial currency stimulating our senses.

• 35:21Neil deGrasse Tyson?

  We buy art that our eyes-

• 35:22Speaker 01

  I've never thought of it described that way.

• 35:24Neil deGrasse Tyson?

  That's right. We listen to music that soothes our ears. We make very tasty foods to soothe our senses. We all love massages because the sense of touch makes us feel good.

• 35:36Speaker 01

  Maybe that's why we're limited to five. We couldn't afford more.

• 35:39Neil deGrasse Tyson?

  Couldn't afford more. And if they had eight senses, I'd ask, "How do you stimulate those other four, the three beyond ours or the..." So I'd take it out of just pure science discoveries and just find out, "What do they do in their cultures to bring joy and happiness to their lives?" We would read poetry. We would embrace art. We would sing a song. That's what I would do.

• 36:00Speaker 01

  Wow. That's beautiful.

• 36:03Neil deGrasse Tyson?

  We've got time for a short one.

• 36:04Speaker 01

  All right, we do, we do. Okay, this is from Mark Fesco. He says, "Surely you've watched the Alien franchise featuring Sigourney Weaver. If we would ever come in contact with a life form such as that, would you support the total annihilation of their species? Or would it bother you on a moral level?" Really, Mark? Really?

• 36:25Neil deGrasse Tyson?

  If it's gonna kill you, or you can kill it, you kill it. I think it's pretty simple, that's a simple thing going on there. I think if you could save one for study, to understand and learn about it, the knowledge of discovery, I think as a scientist, I would always value. But to say, "Let's have it live among us and occasionally it'll take one of us out, but don't kill it for moral reasons", you know, I think morality has a line and it's, "I wanna survive."

• 36:50Speaker 01

  Yes.

• 36:50Neil deGrasse Tyson?

  And if it's me or an alien, it's me. Excuse me. We gotta wrap this up. Leanne, thanks for being on StarTalk Radio.

• 36:57Speaker 01

  No, thank you for having me. I love this.

• 36:59Neil deGrasse Tyson?

  This has been brought to you by, in part by, the grant from the National Science Foundation. I'm Neil deGrasse Tyson. For StarTalk, I'm signing off, bidding you farewell, and compelling you daily to keep looking up.