WEBVTT - SETI: The Search for Extraterrestrial Intelligence, Part 1

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<v Speaker 1>Welcome to stuff to Blow your mind from how Stuff

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<v Speaker 1>Works dot com. Hey you welcome to Stuff of all

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<v Speaker 1>your mind. My name is Robert Lamb and I'm Julie Douglas.

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<v Speaker 1>And you know, when you look at space explorestion, you

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<v Speaker 1>know we're looking outward, but then there's also a lot

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<v Speaker 1>of looking inward. Um. It's just about anything humans do.

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<v Speaker 1>You can sort of make a case for the selfishness

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<v Speaker 1>of it and the self absorption of it. So we

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<v Speaker 1>look out into space because we want to know something

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<v Speaker 1>about ourselves. A lot of the times we want to

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<v Speaker 1>know what's out there because we want to know where

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<v Speaker 1>we fit in. We want to know if there's intelligent

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<v Speaker 1>life or life out there at all, because that puts

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<v Speaker 1>who we are and what we are in some level

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<v Speaker 1>of perspective. And that's one area where set comes into play,

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<v Speaker 1>the search for extraterrestrial intelligence. Right, So, as long as

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<v Speaker 1>there have been humans, um, there has been this question

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<v Speaker 1>of are we alone in the universe? Because you can't

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<v Speaker 1>help but look up in the night sky and say,

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<v Speaker 1>is that it? You know? Is there? Are we unique?

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<v Speaker 1>There are all sorts of questions that roll out here. Now.

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<v Speaker 1>Of course, astrophysicists astrobiologists, um, astronomers are all trying to

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<v Speaker 1>answer this question, and they're looking more though, in the

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<v Speaker 1>infancy infancy of really this possibility of intelligent life. And

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<v Speaker 1>when I say infancy, I'm talking more about Mars and

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<v Speaker 1>the possibility of microbial life there, or Jupiter's moon Europa

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<v Speaker 1>and the presence of water underneath the frozen oceans, or

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<v Speaker 1>liquid hydrocarbon lakes on Saturdays moon Titan. So we have

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<v Speaker 1>to look there first because we know that those are

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<v Speaker 1>sort of the building blocks of microbial life, which then

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<v Speaker 1>evolves into something more significant or complex, I should say. So,

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<v Speaker 1>of course this leads to this question of well, are

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<v Speaker 1>we really unique? Um? Is life the flora and fauna

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<v Speaker 1>on Earth unique to us? Is that it? Um? And

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<v Speaker 1>this is a huge question and we have to unpack

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<v Speaker 1>it a little bit. Yeah. I mean, as we've discussed before,

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<v Speaker 1>when when you're talking about life, I mean, ultimately we

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<v Speaker 1>have the one model to go on. So we inevitably

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<v Speaker 1>we keep coming back to that, what is life and

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<v Speaker 1>so stuff on this planet? What are the parameters for

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<v Speaker 1>life as we have seen it so far as we

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<v Speaker 1>know it? And uh, and what are what's the chemical

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<v Speaker 1>formula for what is required, what elements? When do we

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<v Speaker 1>need to look for? It's uh, I often think about it.

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<v Speaker 1>It's kind of like um, shopping for a new house.

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<v Speaker 1>You know, you're looking at all right now, what what's

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<v Speaker 1>what kind of neighborhood do I want to live in? What? What?

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<v Speaker 1>What do I need to be close enough to? What

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<v Speaker 1>resources need to be nearby to make it agreeable? What?

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<v Speaker 1>What type of neighborhood is is too hostile to me? Uh?

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<v Speaker 1>You know, like one one area is going to be

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<v Speaker 1>too fancy, too too rich, just excluding completely another area, uh,

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<v Speaker 1>might be a war zone. You know. We have to

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<v Speaker 1>say to take all of this into into account even

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<v Speaker 1>when we're looking for extratrustrial life, because we're looking at

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<v Speaker 1>where where else could life exist more or less like

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<v Speaker 1>it exists here, You're right, So we really have to

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<v Speaker 1>turn to ourselves. And we know that the chemical composition

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<v Speaker 1>of earth face life consists of hydrogen, carbon, and oxygen.

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<v Speaker 1>So that accounts for more than of the atoms and

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<v Speaker 1>the human body and in all other known life. So

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<v Speaker 1>of those three, carbon is really the star of the show,

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<v Speaker 1>since it can bond with itself and other molecules really easily,

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<v Speaker 1>and it's a very strong bond. Now, if you kind

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<v Speaker 1>of take the lens here from from humans and um

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<v Speaker 1>and another life on Earth, and you sort of go

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<v Speaker 1>out a little bit into the universe, what do you find?

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<v Speaker 1>You find the most common elements in the universe are hydrogen, helium, carbon,

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<v Speaker 1>and oxygen. Okay, So what is this saying. This is

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<v Speaker 1>saying that, uh, life is not chemically special, especially if

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<v Speaker 1>you consider that the basis of it can be easily

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<v Speaker 1>found in the universe and then harnessed here on Earth.

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<v Speaker 1>And if life on Earth were composed primarily of manganese

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<v Speaker 1>or molly bendum, then we would have excellent reason to

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<v Speaker 1>suspect that we're something special in the universe. But it's not. Yeah,

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<v Speaker 1>all this stuff is everywhere. It's kind of you know,

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<v Speaker 1>it's kind of like you know when you you're a

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<v Speaker 1>certain age and you find this book that you really

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<v Speaker 1>dig and you're like, oh, my goodness, is it the

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<v Speaker 1>most n album? Say it's an album by a group,

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<v Speaker 1>and you're like, how this is the most precious thing? This?

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<v Speaker 1>I love this, this album in this book so much.

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<v Speaker 1>It speaks directly to me. The artist is speaking directly

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<v Speaker 1>to me, and only I can really appreciate it in

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<v Speaker 1>the way that I'm appreciating it now. And then you realize, oh,

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<v Speaker 1>it's a nation nationwide bestseller, or it's it's on the

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<v Speaker 1>top ten Billboard charts, or you know, the went triple

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<v Speaker 1>platinum or whatever, and you realize, oh, actually, this appeals

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<v Speaker 1>to a lot of people, and I am not special

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<v Speaker 1>in liking it. Yeah, and you discover that it's playing

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<v Speaker 1>throughout the universe, right, the same music, and it's the

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<v Speaker 1>same elements, those same ingredients that make us that are

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<v Speaker 1>out there in the stars. But we've talked about this before,

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<v Speaker 1>because you've talked about if his start implodes um, you know,

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<v Speaker 1>it's throwing out all sorts of material into the universe.

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<v Speaker 1>And you know, there's that the great quote by Lawrence

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<v Speaker 1>Cross says, you know the atoms in your right hand

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<v Speaker 1>are in your left hand all came from that one

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<v Speaker 1>star exploding. So it makes sense. This is this is

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<v Speaker 1>the stuff that's making that soup. This is the base

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<v Speaker 1>of the soup. Um. And if you take that logic,

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<v Speaker 1>then you start to say, Okay, it's not unique. This

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<v Speaker 1>is a recipe that could be executed elsewhere on the universe. Yes,

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<v Speaker 1>But of course the thing about recipes. Um, so we

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<v Speaker 1>all know is that it's it's not merely enough to

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<v Speaker 1>know what goes in, but you have to know, uh

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<v Speaker 1>what amounts going You need to know is it is

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<v Speaker 1>it a tablespoon of salt or a teaspoon of salt?

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<v Speaker 1>Um makes the world of difference. Um, are certain substitutions allowed,

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<v Speaker 1>which ones are not? How are you heating it? How

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<v Speaker 1>are you preparing it to make all the difference in

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<v Speaker 1>in the ultimate outcome of the recipe? And likewise there

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<v Speaker 1>is a lot of that to take into account, just

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<v Speaker 1>chemically with with Earth and life on Earth. In his

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<v Speaker 1>book The Autographs, Diyson points out the oxygen thing. You

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<v Speaker 1>need a lot of free oxygen and that needs to

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<v Speaker 1>be supported by some sort of a system on our

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<v Speaker 1>planet's ported of course, by all the vegetation that we

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<v Speaker 1>we have on this planet. So you have to have

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<v Speaker 1>the right circumstances in place to allow the right chemical

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<v Speaker 1>situation to be in order. So evolution is kind of

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<v Speaker 1>like the baking time, right. So if it takes ten

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<v Speaker 1>billion years for a planet become hospitable, then that's ten

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<v Speaker 1>billion years of baking time. And so you have to

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<v Speaker 1>consider that when when we're talking about exo planets, and

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<v Speaker 1>we're talking about them being just the right distance from

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<v Speaker 1>the star or um from a sent or a moon

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<v Speaker 1>to have the correct elements there for the baking. Right,

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<v Speaker 1>that's just one aspect of it. But again, the ingredients

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<v Speaker 1>for the recipe your out there, which makes it so

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<v Speaker 1>tantalizing of a question of whether or not there exists

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<v Speaker 1>other life and intelligent life at that UM. Of course,

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<v Speaker 1>we had to go back to something called the Copernican principle,

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<v Speaker 1>uh to really sort of understand how life may not

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<v Speaker 1>be that special in the first place. Yeah. And then this,

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<v Speaker 1>of course kind from should say chemical life. Yes, this

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<v Speaker 1>of course comes to us from a mid Polish astronomer,

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<v Speaker 1>Nicolas Copernicus. Um and uh. And basically the whole deal

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<v Speaker 1>here is that we're nothing special, and that you cannot

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<v Speaker 1>enter a scientific analysis of the universe with the idea

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<v Speaker 1>that we're something special. There are a number of different

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<v Speaker 1>things that spin off of this, For instance, UM. In

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<v Speaker 1>nineteen seventy four, astronomer Brandon Carter tackled the quandary of

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<v Speaker 1>our anti anthropic coincidence, the idea that there are a

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<v Speaker 1>number of coincidences that supposedly make life on Earth possible UM,

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<v Speaker 1>and he hypothesized that these coincidence are part of the

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<v Speaker 1>universe very structure, and the chance has nothing to do

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<v Speaker 1>with it. He proposed two variants, the most important what

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<v Speaker 1>we're talking about here is the strong anthropic principle UH.

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<v Speaker 1>And in this he drew on the Copernican principle UH,

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<v Speaker 1>which again states that there's nothing special or privileged about

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<v Speaker 1>Earth or humanity. Uh. We live in a universe capable

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<v Speaker 1>of supporting life than than only life supporting universes are possible.

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<v Speaker 1>You can really go down the rabbit hole with this,

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<v Speaker 1>But essentially it's about putting aside any idea that we

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<v Speaker 1>are special. Again, the the the album is a hit

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<v Speaker 1>around the universe that the building blocks are out there. Uh.

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<v Speaker 1>We can't enter into any kind of an analysis of

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<v Speaker 1>or even of a pondering of life else where in

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<v Speaker 1>the universe if we're thinking that we're special in some way. Yeah.

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<v Speaker 1>And what I really like about the comparonic in principle

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<v Speaker 1>is that it does show an evolution of understanding of

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<v Speaker 1>our place in the universe, because you know, Comparnicas of

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<v Speaker 1>sitting there saying at a time where everybody was thinking

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<v Speaker 1>the opposite is saying, hey, the Earth is not the

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<v Speaker 1>center of our solar system. And so, of course that

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<v Speaker 1>was a crazy thought at the time. Yeah, because for

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<v Speaker 1>the longest, Yeah, Earth has to be the center. We're

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<v Speaker 1>the center God's blessed creation. So we should be right

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<v Speaker 1>there at the center. How can this whole thing not

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<v Speaker 1>be about us? Right? We are it right? Um. But

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<v Speaker 1>then there's this idea that evolves even more like, okay, hey,

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<v Speaker 1>well we're not the center of the Solar system in

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<v Speaker 1>the Milky Way, by the way, our Milky Way, our

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<v Speaker 1>galaxy is not the center of universe. In fact, we're

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<v Speaker 1>not quite sure what the center is. Is there a center? Um?

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<v Speaker 1>So you really do see this, This understanding become much

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<v Speaker 1>more complex and nuanced as we get more and more

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<v Speaker 1>data from the world around us, because now we understand

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<v Speaker 1>that Earth is just one of billions of planets that

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<v Speaker 1>are all bathing in the same sort of primary chemicals. Um.

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<v Speaker 1>So that gets us to this area called the Drake equation.

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<v Speaker 1>So we really have to talk about this before we

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<v Speaker 1>can even sort of say, okay, we'll do aliens exist,

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<v Speaker 1>How would they exist? How would we contact them? All? Right,

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<v Speaker 1>We're gonna take a quick break and when we come

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<v Speaker 1>back even more on the search for extraterrestrial intelligence. Yes,

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<v Speaker 1>the Drake equation. So the Drake equation is pretty widely known.

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<v Speaker 1>It's been spun off into a number of interesting little

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<v Speaker 1>side projects, like there was a there's a really good

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<v Speaker 1>episode of This American Life where that's a team of

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<v Speaker 1>scientists try to use the Drake equation to determine whether

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<v Speaker 1>they have a true love match out there in the

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<v Speaker 1>world waiting for them, as opposed to is there another

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<v Speaker 1>life form or other life forms elsewhere in the galaxy. Yeah,

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<v Speaker 1>because I want to say this just at the front here,

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<v Speaker 1>that the Drake equation is not something that is solvable.

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<v Speaker 1>It is it's really about probabilities and how to organize

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<v Speaker 1>our thoughts about the data that we have in the

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<v Speaker 1>missing data. Yeah, it's about taking the one big question,

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<v Speaker 1>the one big probability is their life else from in

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<v Speaker 1>the universe, and breaking it down into smaller questions, smaller

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<v Speaker 1>probabilities that we can tackle individually. So the entire equation

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<v Speaker 1>looks like this, and and this is not gonna all

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<v Speaker 1>make a lot of sense, but just in the in

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<v Speaker 1>the in the interest of getting out there, it is

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<v Speaker 1>in equals our star multiplied by F sub p multiplied

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<v Speaker 1>by in sub multiplied by F sub F sub l

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<v Speaker 1>multiplied by F sub i multiplied by F subc multiplied

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<v Speaker 1>by capital l. And so all those numbers must by

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<v Speaker 1>together help us to estimate the number in of technical

0:11:11.840 --> 0:11:14.839
<v Speaker 1>logical civilizations that might be able to detect us right now. Now,

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<v Speaker 1>if you guys all bear with me, let me unpack

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<v Speaker 1>that a little bit, because I do think it's interesting.

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<v Speaker 1>Um our star is the rate at which stars have

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<v Speaker 1>been born in the Milky Way galaxy over the last

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<v Speaker 1>few billion years. That stars per year, okay, And then

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<v Speaker 1>all the f factors in this are fractions. So F

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<v Speaker 1>sub p is a fraction of stars that have planets,

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<v Speaker 1>and sub e is the average number of habitable planets

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<v Speaker 1>in any planetary system. F sub l is the fraction

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<v Speaker 1>of planets on which life actually begins. F sub i

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<v Speaker 1>is a fraction of all those life forms that develop intelligency.

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<v Speaker 1>How this becomes Tinier and jiner um. And then F

0:11:52.280 --> 0:11:55.320
<v Speaker 1>sub c is the fraction of intelligent life that develop

0:11:55.480 --> 0:12:00.959
<v Speaker 1>a civilization that uses some sort of transmitting technology. Finally, L,

0:12:01.000 --> 0:12:03.120
<v Speaker 1>which is really important here, and we'll talk more about

0:12:03.160 --> 0:12:06.280
<v Speaker 1>this later l is the longevity factor. On average, how

0:12:06.280 --> 0:12:09.960
<v Speaker 1>many years do those transmitters continue to operate, because, as

0:12:10.040 --> 0:12:13.120
<v Speaker 1>we know, civilizations come and go. Yeah, Like I kind

0:12:13.120 --> 0:12:14.360
<v Speaker 1>of like to think of it in terms of a

0:12:14.440 --> 0:12:17.080
<v Speaker 1>video store, like you know, and some of you may ask,

0:12:17.120 --> 0:12:19.800
<v Speaker 1>what what what is that? Because they are starting to

0:12:19.840 --> 0:12:22.640
<v Speaker 1>disappear more and more. But like in the Atlanta we

0:12:22.640 --> 0:12:25.240
<v Speaker 1>have this really cool video store called Video Drome. I

0:12:25.280 --> 0:12:27.840
<v Speaker 1>still like to go there just to brows around for

0:12:27.920 --> 0:12:30.600
<v Speaker 1>nostalgia and nothing else. But you know, I walk into

0:12:30.600 --> 0:12:33.320
<v Speaker 1>a video store and I have, you know, X number

0:12:33.360 --> 0:12:36.480
<v Speaker 1>of videos at my disposal for possible rent. But then

0:12:36.480 --> 0:12:38.480
<v Speaker 1>you have to you have to carve that down all right,

0:12:38.520 --> 0:12:40.480
<v Speaker 1>of all the videos here, I can only check out

0:12:40.480 --> 0:12:43.319
<v Speaker 1>ones that are checked in, so that dude decreases the number.

0:12:43.760 --> 0:12:47.000
<v Speaker 1>Then maybe I'm only interested in seeing an English language

0:12:47.000 --> 0:12:49.040
<v Speaker 1>film because I don't want to read subtitles tonight, So

0:12:49.080 --> 0:12:51.040
<v Speaker 1>then we have to cut that down. Then I must

0:12:51.040 --> 0:12:53.520
<v Speaker 1>say I'm only interested in seeing a horror movie, so

0:12:53.600 --> 0:12:55.559
<v Speaker 1>that cuts it down even more. And then I only

0:12:55.600 --> 0:12:57.720
<v Speaker 1>interested in seeing a horror movie that I haven't already seen,

0:12:57.800 --> 0:12:59.480
<v Speaker 1>so that cuts it down even more. And again you

0:12:59.520 --> 0:13:02.439
<v Speaker 1>just get down to there are x number of films

0:13:02.480 --> 0:13:05.680
<v Speaker 1>that I could potentially rent this evening. Now, what I

0:13:05.679 --> 0:13:08.959
<v Speaker 1>think is cool about this dract equation is that, yes,

0:13:09.040 --> 0:13:11.080
<v Speaker 1>there's no righting answer right now, and this is just

0:13:11.120 --> 0:13:13.280
<v Speaker 1>a way of organizing information because a lot of it

0:13:13.280 --> 0:13:15.280
<v Speaker 1>does depend on who's plugging in the data and why

0:13:15.600 --> 0:13:18.240
<v Speaker 1>right in the same way that my data I plug

0:13:18.240 --> 0:13:20.920
<v Speaker 1>into this video drum equation could be different one day

0:13:20.920 --> 0:13:23.160
<v Speaker 1>from the next. The deal is, though, is that astronomers

0:13:23.160 --> 0:13:26.560
<v Speaker 1>are actually getting at this equation right. They've already tried

0:13:26.600 --> 0:13:29.600
<v Speaker 1>to figure out about three of those different fractions, So

0:13:29.920 --> 0:13:32.840
<v Speaker 1>they're trying to figure out the fraction of stars planets,

0:13:33.160 --> 0:13:37.240
<v Speaker 1>the average number of habitable planets, and the fraction of

0:13:37.240 --> 0:13:40.320
<v Speaker 1>planets on which life actually begins. So they're getting to that.

0:13:40.400 --> 0:13:43.440
<v Speaker 1>So when I talk about exit planets that are habitable

0:13:43.840 --> 0:13:46.440
<v Speaker 1>and that goldilocks not too hot, not too cold, that'

0:13:46.440 --> 0:13:48.320
<v Speaker 1>from one aspect of it that they're beginning to collect

0:13:48.400 --> 0:13:52.360
<v Speaker 1>data on um and they're beginning to say like, okay, well,

0:13:52.640 --> 0:13:55.760
<v Speaker 1>now we can get these chemical signatures and try to

0:13:55.800 --> 0:13:58.480
<v Speaker 1>figure out, you know, how much carbon is being produced there,

0:13:58.520 --> 0:14:03.120
<v Speaker 1>how much method sane which you know something we'll talk

0:14:03.200 --> 0:14:06.080
<v Speaker 1>more about as pretty plentiful here on Earth, and that's

0:14:06.080 --> 0:14:08.320
<v Speaker 1>a that's a huge signal if there's something going on

0:14:08.320 --> 0:14:12.880
<v Speaker 1>on that planet, right probably probably cows as well as

0:14:12.920 --> 0:14:16.319
<v Speaker 1>other you know, factors that that create methane that I

0:14:16.360 --> 0:14:19.080
<v Speaker 1>won't go into. Uh, But anyway, my point is is

0:14:19.120 --> 0:14:21.160
<v Speaker 1>that yes, this is, uh, this is somewhat of a

0:14:21.160 --> 0:14:25.000
<v Speaker 1>thought experiment, but astronomers are scratching away at it and

0:14:25.000 --> 0:14:27.960
<v Speaker 1>they're getting some concrete information in there. Yeah. Um, I

0:14:27.960 --> 0:14:31.640
<v Speaker 1>mean historically whether the estimate the results have varied again

0:14:31.680 --> 0:14:33.840
<v Speaker 1>depending on what's going into it, and they varied from

0:14:33.960 --> 0:14:38.680
<v Speaker 1>there being one one but one civilization out there two millions.

0:14:38.680 --> 0:14:41.440
<v Speaker 1>So yeah, right, Again, there's a lot of data that

0:14:41.480 --> 0:14:44.440
<v Speaker 1>needs to be plugged in here, but astronomers are if

0:14:44.480 --> 0:14:47.120
<v Speaker 1>if you will, plugging away at that. Now, I wanted

0:14:47.160 --> 0:14:49.960
<v Speaker 1>to mention the Fermi paradox, and this is something I

0:14:50.280 --> 0:14:52.760
<v Speaker 1>want you guys to all put in your back pocket

0:14:52.760 --> 0:14:54.920
<v Speaker 1>as you consider all the other information that we talked

0:14:54.920 --> 0:14:58.120
<v Speaker 1>about today. The Fermi paradox is from the Noble Prize

0:14:58.160 --> 0:15:02.040
<v Speaker 1>winning physicist and Rico Fantom and he reasoned that if

0:15:02.080 --> 0:15:05.840
<v Speaker 1>it takes life billions of years, should develop intelligence and

0:15:06.160 --> 0:15:08.960
<v Speaker 1>signal or travel to the stars. And if there are

0:15:09.080 --> 0:15:12.880
<v Speaker 1>billions of worlds in the universe, and if the universe

0:15:12.960 --> 0:15:16.240
<v Speaker 1>is over thirteen billion years old, then why haven't we

0:15:16.400 --> 0:15:19.800
<v Speaker 1>been visited by an extra terrestrial or why isn't the

0:15:19.840 --> 0:15:25.000
<v Speaker 1>galaxy crawling with extraterrestrials. This is something we'll get too later.

0:15:25.160 --> 0:15:27.640
<v Speaker 1>But that's that's a good question, right, yeah, I mean

0:15:27.680 --> 0:15:30.000
<v Speaker 1>it's Stephen Hawking brought up the same thing with time travel.

0:15:30.440 --> 0:15:33.840
<v Speaker 1>You have if time travel was possible, is possible, will

0:15:33.880 --> 0:15:36.120
<v Speaker 1>be possible? When I have we not been visited by

0:15:36.120 --> 0:15:38.360
<v Speaker 1>a time traveler. Like it's just kind of a basic,

0:15:39.200 --> 0:15:43.040
<v Speaker 1>you know, show me level of of of analysis. Okay,

0:15:43.040 --> 0:15:45.920
<v Speaker 1>they're aliens, great, show me one, show me the alien

0:15:46.280 --> 0:15:48.000
<v Speaker 1>put it on the table for me to see because

0:15:48.000 --> 0:15:53.080
<v Speaker 1>the time traveler erased our memory, and certainly you could,

0:15:53.120 --> 0:15:56.000
<v Speaker 1>you can, you can roll out varying levels of conspiracy

0:15:56.200 --> 0:15:58.520
<v Speaker 1>and and explanations on top of it. But you know,

0:15:58.560 --> 0:16:00.520
<v Speaker 1>at the at the very root, it's it's a question

0:16:00.560 --> 0:16:02.360
<v Speaker 1>of all right, if they're aliens, then we should have

0:16:02.440 --> 0:16:04.480
<v Speaker 1>seen them, We should see them, and then you can

0:16:04.600 --> 0:16:06.640
<v Speaker 1>you can apply your own excuses as to why don't

0:16:06.640 --> 0:16:09.360
<v Speaker 1>we have not Alright, Well, On that note, we're going

0:16:09.440 --> 0:16:12.280
<v Speaker 1>to actually call this an episode. We're splitting the SETI

0:16:12.840 --> 0:16:15.360
<v Speaker 1>episode up into two episodes, so this was part one.

0:16:16.080 --> 0:16:18.800
<v Speaker 1>Part two will publish very shortly, so be on the

0:16:18.840 --> 0:16:21.040
<v Speaker 1>lookout for that in the time being. If you have

0:16:21.440 --> 0:16:24.560
<v Speaker 1>any kind of feedback on part one, you can find

0:16:24.600 --> 0:16:26.240
<v Speaker 1>us on Facebook and you can find us on tumbler.

0:16:26.280 --> 0:16:27.680
<v Speaker 1>We are stuff to blow your mind on both of

0:16:27.680 --> 0:16:30.880
<v Speaker 1>those and we use the handle blow the Mind on Twitter,

0:16:31.240 --> 0:16:33.320
<v Speaker 1>and you can always drop us a line at below

0:16:33.400 --> 0:16:42.280
<v Speaker 1>the Mind at Discovery dot com. For more on this

0:16:42.440 --> 0:16:44.960
<v Speaker 1>and thousands of other topics, Is it how Stuff Works

0:16:44.960 --> 0:16:49.480
<v Speaker 1>dot com