talk a little bit about looking for life

in general but in fact I work at this

SETI Institute SETI and because there's

at least one person the audience who had

the acuity to ask what does that mean

its search for extra turn it its search

for extraterrestrial intelligence so

this is more than just looking for life

there's a lot of people that look for

life where I work at the SETI Institute

95% of the scientists are looking for

life but they don't expect it to hold up

its side of the conversation they're

looking for dumb life you know microbes

on Mars something like that okay so

we're looking for intelligent life I

don't know why this thing is changing

automatically but maybe that's okay all

right we used to think that there was

life nearby a hundred years ago most of

you are probably not old enough to

remember that but it was thought that

there was plenty of life in the solar

system and even intelligent life this is

Percival Lowell some of you may

recognize and any of you from

Massachusetts will know the name Lowe

because he came from a Boston Brahmin

family right and he was interested I

mean you know he had money he didn't

really have to take any job when he

graduated he could just you know lie

back and think of England or something

but in fact he was interested in

astronomy and rather than trying to get

you know tenure at some third-rate

university he just built his own

Observatory now he studied mathematics

he was said to have been the smartest

student at Harvard ever had mind you

it's only Harvard but so here he is at

the modestly named Lowell Observatory on

a night in 1914 actually and you know it

doesn't show anyway 1914 and in fact he

was trying to check out the Mars canals

not in this photo he was actually

looking at Venus here but it doesn't

matter the Martian canals they weren't

canals on Venus that he knew about

Martian canals because those had been

seen in the late 19th century even the

earlier part of the 19th century by

Italian astronomers and he believed it

he thought he could see them and in fact

here here some of his handiwork here he

mapped four hundred of these canals

there was obviously this vast hydraulic

civilization just 35 million miles from

downtown Atlanta ok he wrote books about

this he was a good writer he was an

excellent speaker

the public believe this now there were

very few astronomers who believed it at

the time because they would look through

their telescopes and they would not see

the canals but what Lowell said was you

know what your problem is and I'm sure

these people had many problems but he

said your problem is you're not in

Flagstaff Arizona where the atmosphere

is more stable clear of seeing better

seeing and so forth

I point out that if this photos you can

see in 1914 when this photo was made you

would put on a suit to sit alone all

night in a dark dome and look at Venus

you don't do that anymore and in fact

his wife who was about 20 or 30 years

younger than he was consonants she

didn't find this all that interesting

she stayed back in Boston we don't have

any photos of what she was doing in the

evening but not this presumably okay so

that's how people look further for

intelligent life in the universe back

then this is a kind of a modern photo of

Mars I don't know if you can see it but

here it is and you can see this giant

canal going across there but of course

it's a natural feature it's in the

Mariner Valley from one side to the

other is this is more or less the

distance from Seattle to Atlanta okay so

this is 200 times the area to Grand

Canyon any of you who are interested in

a career in real estate may want to

consider buying property here because

undoubtedly in another hundred years

it'll be a great tourist attraction but

of course this is this is naturally

cause the canals were not there okay

nonetheless we continue to look for life

on Mars this is a NASA impression of the

Curiosity rover not that the Curiosity

rover is actually looking for life but

it's looking for places to look for life

and before this there was there was a

reconnaissance done to look for where we

should look for looking for life and

yeah here it is this is what it really

looks like okay and it's going up this

mountain in the back Mount sharp now you

might wonder well why is it gonna climb

that mountain it's not just because it's

there which might be a you know good

motivation in some cases but not here

it's because it's got sediment clearly

sedimentary rock and that means that if

you can get to the bottom of the

mountain and it's looking at rockets on

the order of three or four billion years

old and then it goes up a little bit and

it's only 2 billion years and 1 billion

and gets to the top it's kind of

contemporary rock the idea is

is to find where to dig to look for

fossilized microbes or something else

like that okay so that's what's

happening on Mars there's lots of stuff

happening on Mars Mars remains everyone

favorite inhabited planet particularly

so because there been some things

discovered recently that suggests maybe

Mars really is a good candidate for life

or maybe was a good candidate for life

there's been methane found in the

atmosphere those of you who study

chemistry know that methane is made out

of ping-pong balls and sticks the ch4

here now the thing about methane is it's

you know it's an exhaust gas of

methanogenic bacteria you know bacteria

some bacteria can make methane if you

live next to a garbage dump as I do then

you will know that that's true the other

thing however is that so if you find

methane on Mars you might say this

bacteria under the ground

two things about that it's not the only

way to make methane you can also make it

a biotic li which is to say with you

know just hot rock really and the the

second thing is that if you were to

release some methane on the into the

atmosphere of Mars right and wait for

hundred years it would all be gone

because of the ultraviolet light from

the Sun which would break it all apart

so the question is this methane seems to

be real it's got to be recent methane

because it gets destroyed on timescales

of only a few hundred years and if it's

recent methane is it biology or is it

geology and the answer to that is we

don't know yet here's just a map of some

of the methane found on Mars so it's

there this was controversy of maybe a

year to ago we didn't know if the

methane was for real but it is for real

so the question is what's making the

methane here's something else

interesting bout Mars I want to talk too

much about Mars but I am going to

alright here's a this is a result from

the Europeans the Mars Express orbiter

z' had some low frequency radar and it

looked at this patch of Mars here's a

South Pole over there for those of you

are planning a weekend trip to Mars at

this area here it found a reflection

from the low-frequency radar now the

thing about low-frequency radar is that

it'll actually penetrate the ground it's

very hard to look under the ground with

radar because radar doesn't doesn't

penetrate their ground very well and it

certainly doesn't penetrate oceans very

well ask the US Navy it's very hard to

find submarines because

can't just his radar anyhow what they

found was here's a radar reflection and

you see this layer here very bright that

was getting a lot of radar back from

something about a mile under the surface

and the question is what do you think it

is Bob well who knows what it is maybe

somebody left a big aluminum plate down

there but more likely its water does

that would reflect the radar okay

and so the claim here although it's it's

a tentative claim the claim was that

there's a big underground lake on Mars

and if that's true that Lake has

probably been there for billions of

years or it could have been so if life

ever

you know began on Mars that's maybe

where to find it so if you want to find

life in the universe and we haven't done

that yet but if you want to find any

life in the universe maybe your best

strategy is to get you know I know get

some drilling rig guys you know from

Louisiana take them to Mars and have

them drilled down there okay and and

suck up some of the water and look at it

under a microscope okay by the way I

might point out that if you type into

Google life on Mars you'll find that

many people have found life on Mars okay

and and the way they do that is by

looking through the rover photos and

over analyzing them for example anybody

been to Copenhagen if you have you know

the lonely little mermaid has is one guy

in the audience this is this is kind of

like the White House staff they have an

audience of one all right for some

reason the Martians when they were there

built this replica of the lonely little

mermaid statue in Copenhagen there it is

it's only about you know five

centimeters higher or something but I

don't know why they do that there are

other things like this here's a Nazi

helmet on Mars

apparently the Vermont went to Mars not

many people know that but you know they

check the web you'll find lots of stuff

what else do we have

oh yeah there was this okay so clearly

these are all natural phenomena and we

haven't found life on Mars yet okay

maybe a better place to look for life in

the solar system anyhow might be this

moon of Saturn Enceladus is a model of

what we know about Enceladus I think we

know in any case it's a small moon it's

not as big as our own moon but it has

this layer of liquid of water underneath

the surface there so a hidden ocean

there's a lot of a lot of ice in the

outer solar system and some of it is

squirting through the cracks they're

making a what you might call ice geysers

so shooting ice into space in fact

here's a here's a photo made by the

Cassini mission and believe this is

Saturn soda it's a Cassini mission and

you can see these plumes of ice coming

out through the cracks now why is that

interesting this may be the easy way to

find life if there's life down there in

that big body of water underneath and it

could be you might say uh how is it

making a living I mean there's no Sun

right so you can't do photosynthesis but

of course there are chemical reactions

that can in fact support life if you go

outside tonight and drill a mile deep

hole here on the campus and pull up the

muck the bottom of that and look at that

under microscope you'll find life right

and clearly that's not living on

photosynthesis

it's a various reactions mostly in buyer

in involving iron and stuff like that so

maybe the quickest way to find life in

the solar system it's just to send a

flyby mission to Enceladus and grab some

of this stuff coming out of it and then

bring that back to earth and look at

that okay so they're people I know some

people at NASA Ames Research Center I

know some of you are familiar with NASA

Ames Research Center who have decided

Mars it's okay but it's so yesterday

they want to in fact go to Enceladus

that may be the quickest way to find

life and and this is just a you know

rural rogues gallery of other places in

our solar system where you might have

well almost certainly do have conditions

for life doesn't mean there is life but

if you have the conditions for life why

not look and these are all places you

could

with a rocket so when you talk about

looking for life beyond Earth which is

NASA is very interested in the public is

very interested in three of you are

interested in it if you're if that's

what you want to do these are the places

you would go however if you do find

biology it's almost surely going to be

microbial right so at the SETI Institute

96% of the researchers are doing this

kind of stuff and 4% are looking for the

kind of life that could hold up its side

of the conversation

right intelligent life so that's what

I'll talk about for the rest so you

can't look in our solar system but there

are plenty of other solar systems this

is a from a website that's maintained by

the University of Puerto Rico and they

they keep a list of all the possibly

habitable worlds in fact I think all the

exoplanets but these are the ones that

they have on their front page as the

leading candidates for being habitable

planets now you might say well what does

it mean to be habitable well you'd want

to begin with maybe temperatures half of

what they have in Atlanta you know you

want liquid oceans there's all that

stuff okay and there's no there's no

knowledge about whether any of these

worlds have that but they could they're

the right size they're at the right

distance from their home stars so the

water doesn't all evaporate right away

doesn't all boil away doesn't all freeze

solid anything like that but of course

the details you see in this rendering

are in fact the work of imaginative

artists no have you there's no actual

data in that but so they're a couple of

dozen right here and you might say well

that's a lot of candidates well it's not

right I mean keep in mind if you're

looking for life if you were a Klingon

and you had a SETI experiments to look

for life on Earth

you could have aimed antennas at earth

for four and a half billion years

without ever picking up I Love Lucy or

any other kind of entertainment right so

the fact that you have a couple of dozen

of these things nice interesting but it

isn't going to guarantee that you're

gonna find anything even if intelligent

life is very common it depends on how

long intelligent life lasts if it lasts

or a very long time then the chances for

any given world to have intelligence

might be pretty good pretty good

but if life has so many young people

seem to think

once it gets intelligent heads

immediately to hell in a handbasket

we're gonna self-destruct within 20

years I don't know I the Millennials

think this maybe they don't want to go

to work I don't know what it is but well

whatever if that's your point of view in

life then of course you're not going to

find many candidates where there's

intelligent life now we could maybe up

the the chances a little bit by using

the James Webb Space Telescope assuming

that it gets launched in some reasonably

near future because it would be able to

examine the atmospheres of some of these

nearby planets if they happen to be

aligned correctly so they pass in front

of their stars so you know what's in

front of the star the light you see is

passing through obviously there's direct

sunlight but there's also the light that

goes through the atmosphere and then

when it goes behind it you know you

don't get that atmospheric contribution

to the spectrum so in this case you can

subtract one from the other and in

principle you could find maybe methane

or oxygen in the atmosphere right in

this room 21% of the year was oxygen

before you guys got here right began

using it all up all right now where's

that oxygen come from yay well I it's

always been here said no of course it

hasn't always been here if you'd visited

the earth three four billion years ago

very little oxygen in the atmosphere but

there was a big oxidation event that

began about two billion years ago and it

was because of the invention of

photosynthesis so you know if you find

oxygen in somebody else's atmosphere you

exact I don't know what it is but there

could be photosynthesis so that's a good

way to find cabbage in space if that's

your intention methane methane is as

suggested produced by microbes also

there's methane in the atmosphere and a

lot of it is due to what's politely

called bovine flatulence or porcine

flatulence so if you found methane you

could say pigs in space I mean so this

this is all set that's going to happen

in the next ten years so this is these

are the kinds of things where we point

our antennas at star systems where we

think they have worlds that have all

these things that you know we have here

on earth in other words we look for

analogues to what we know we look for

analogs to life on earth we use this set

of antennas in the Cascade Mountains of

California you

I wonder why it's located there this is

about 300 miles north of San Francisco

I'm sure many of you are familiar with

San Francisco personally I have signed

the petition to have San Francisco towed

ten miles out to sea and sunk but I'm

not that that feeling isn't universal

there are people who love San Francisco

but this is this is located here to

avoid the San Francisco because with

these Cascade Mountains here they're all

volcanic things it blocks all the

interference all the radio noise from

San Francisco which has millions of

people of course and yeah it's called

the Allen telescope array Paul Allen

co-founder Microsoft Corporation paid

for the R&D and the construction of 42

of these things the idea is to build

hundreds that's a money issue I'm not

going to talk to you about money because

young people are totally oblivious to

money but that will you know if that

will change all right what else what am

I doing here okay so this is Frank Drake

he comes in every morning he writes this

equation on the board we don't know what

it means but Frank Drake Frank Drake

back in 1960 did the first modern SETI

experiment okay he used in the antenna

in West Virginia not terribly far from

here and he pointed it over the course

of a couple of weeks in the direction of

two nearby stars hoping to eavesdrop on

signals from et now what kind of a

signal was he looking for many people

say oh well odd obviously you're looking

for prime numbers or maybe the Fibonacci

series or maybe the value of pi right

which would be as I mentioned earlier

this afternoon if they sent the value of

pi I'd be really disappointed here's the

society that's undoubtedly way ahead of

ours and they send me something that I

learned in seventh grade okay so it's

probably not gonna be the value of pi

but in any case we're not sensitive to

any of that that's the message what we

try and do is simply find a narrowband

component of the signal to tell us that

they're on the air okay all right that's

a technical thing but he was doing that

back in 1960 with a receiver that only

picked up one channel one frequency at a

time and he would turn the radio dial

with a little motor that's how he did it

now

a question that if Frank gets a lot and

actually all of us was okay dr. Drake

you've been looking for et you haven't

found him so far when you gonna find him

and when I first heard that when I first

came to the City Institute this was just

before the civil war broke out when I

first went there and I would listen to

what Frank said and you know I thought

he was gonna say well of course we don't

know but he didn't say that he gave some

number we're gonna find him within a few

years right and then I I listened to it

when he asked Jill tarter that and she

had some other number and other somebody

else had another number and I plotted up

these numbers and it turned out they

correlated very well with the number of

years until these people were going to

retire okay so it's all wishful thinking

okay so I'm gonna see if I can do better

than that this is this is a plot that

shows the speed of SETI searches since

Frank Drake's first experiment back in

1960 so it's some metric it's actually

related to the processing power of the

computers being used so how quickly we

can look for this through this haystack

of the cosmos looking for a needle and

as you can see it's going up and for

those of you who are conscious both of

you it's you know this is a semi-log

plot right which means that it's going

up exponentially a word that the media

now routinely abuses okay so it follows

what I'll call what's called Moore's Law

and as I mentioned earlier today Moore's

law simply says this is this was an

observation by Gordon Moore at the Intel

Corporation back in the 1960s that the

number of you know gates you can get on

a chip doubles every 18 months okay that

was true then it's still true today more

or less what that means is that you have

to you know trade in your computer every

couple of years for a new one not

because it's broken not because it is it

doesn't look just as shiny as it did the

day you bought it but because it's

obsolete and it won't run the software

that you try and use on it okay so

that's Moore's law and that's an

economic law that's because the

companies in this Silicon Valley where I

live

know that your computer isn't gonna wear

out it's not like a car right I mean it

isn't like the auto companies

encourage the use of salt in streets

where where it snows you know we we got

to sell them new cars no here they don't

wear out they're just sitting there on

the floor of your office right they look

just as good as they ever did and they

still work just as well as they ever did

okay but the idea is that they want to

sell you a new one so they keep making

them faster and faster now the benefit

to us is that well faster and faster

means we can look through the sky faster

and faster that's a technical story

which I will spare you but it does mean

that the SETI experiments being done

today are equivalent to all the SETI

experiments done up to this time right

in terms of how many data points are

collected so it's like okay we're

looking for a needle in a haystack and

we start out with a teaspoon about two

years later we got a tablespoon and then

two years after that we got a small

shovel and then you know and after 20

years you have a skip loader right so

that's why I have bet everybody a cup of

coffee that will find et within two

dozen years mainly because of this

because within two thousand years we

will have looked at a million star

systems as of today we've looked at

thousands we will look at have three

orders of magnitude more now I'm going

to talk to a little bit I mean this gets

very speculative but on the other hand

maybe that's refreshing after what

you've just heard okay what would ET be

like now this is what Hollywood thinks

et would be like the only thing that I

find in common between all the

depictions of ET in the movies is that

they always have a lot of mucus sure why

that is but it digests the problem

something okay yeah we have a lot of

mucus now Mike my colleagues are not

very interested in what et looks like to

be honest you know they say I don't care

what he looks like as long as he bill a

transmitter that we can we can pick up

and you know that sounds right but I

think it's wrong because if you don't

think a little bit about what et might

be like you might look for the entirely

wrong thing okay we assume that et is

sort of like us okay I mean maybe there

little gray guys with big eyeballs and

no hair no clothes no names no pets no

sense of humor maybe maybe those are the

guys you always see but those guys who

look like you right and there might not

look like us I don't care so much about

that but they may not be like us

might not be that there's some sort of

sauce squishy critter and they're

billions of them living on some planet

and they've got some technology and they

built some transmitters for whatever

purpose the problem is this these are

the things we assume but those are all

the kinds of things you would assume we

assume that they're going to be more

advanced than we are you might say well

why why couldn't they be less advanced

than we are well of course they could be

but you're never gonna hear from those

guys this is a very strong selection

effect unless they're at Lisa's advanced

technologically as we are they're not

building a big transformation you're

never gonna hear from them right I mean

the Klingons out there might be you know

looking for signals coming from earth

they're never gonna find in the and

earth all's they never would have found

him Neanderthals never did anything that

was you know obvious enough from a

hundred light-years that they could have

been found so if we find anything you

can be sure they're more advanced than

we are and by the way in the movies the

aliens always come to earth right

because they're interested in flattening

Los Angeles to begin with now as a

resident of Northern California I really

don't have any problem with that but on

the other hand would hello Margo some

Southern California says she might but

you know that's a very expensive project

and what does it get him hey we

flattened Los Angeles well that was

worth three hundred trillion galactic

cruzeiro's glad you did that they're

more advanced than we are

technologically yes and that means that

we imagine them as having all this

high-tech you know stuff and they can go

very much faster than our Rockets can

and all that stuff but we're still

imagining that there were like us and

the movies we always defeat them by the

way you might ask how realistic that is

but on the other hand so if you really

want to think well what are they really

gonna be like well you could just

extrapolate well we think we're gonna be

like say a hundred thousand years to now

or something okay here's your standard

alien these are the ones that the a and

movies always use and a biologist from

Emory by the way pointed out to me years

ago that well Seth you know who that is

I said sure that's an alien see then uh

no that's a projection of what we think

we are gonna be like in 50 thousand

hundred thousand years right I mean you

know sure I mean he's got eyes we've got

I mean small noses we're losing

our olfactory since small mouths because

we're losing our dentition right small

stature because these guys don't load

trucks for a living I mean judging from

the eyes which we know only thing to

have gotten bigger you know they're all

designing websites okay okay so that's

something that struck me when I look at

this the other day there's no you know

sort of no whites to their eyes you know

there are critters that don't have white

satirizing they say well who cares but

you don't care if you're a social

critter you need the whites to the eyes

so you can see where the guy next to you

is looking is he looking at you is he

looking at you know your mate

maybe I don't know what are you see

you're gonna grab that steak what so

it's important in it I think for social

animals to have whites of the eyes it's

just a sign probably wrong but okay all

right so this is what we think they're

going to be like but and you know this

is what they're gonna be like in terms

of their characteristics these are all

the sorts of things you could expect or

at least most people do this last one I

think is important appendages to wield a

soldering iron

the scientist from Emory who was telling

me about the aliens actually studies

dolphins and she maintains that they're

very very clever I don't doubt that I

don't own you I don't have any dolphin

friends so I don't know but and they

don't write great books they're gonna

tell you that but you maybe they're

clever they have big brains relative to

their bodies but they have a hard time

picking up a screwdriver okay and I

think that that's important if you can't

use tools easily and you're not gonna

build a radio transmitter I mean even

leaving aside the fact that they mostly

live underwater or you know radio waves

don't even have an easy time getting

through so yeah but these are the things

we expect oh stereovision

okay that's what we expect and this is

the other thing we expect this is a plot

I'm told never to show plot so I'm

showing these plots this is your brain

size right the volume of your brain as a

function of time long ago today all

right so that's three million years ago

when your brain not you personally but

you know when brains were this is our

Australopithecus or whatever you know

some ancestor of Homo sapiens your brain

suede 500 Rams they way to pound about a

million years ago your brain way to two

pounds today your brain weighs three

pounds this is something you can verify

for yourself I suppose if you wear your

brains in the morning

okay and and the assumption for et is

that this curve just keeps going up you

know through the roof here and that our

descendants will have ten-pound brains

so ET will probably have a 10-pound rein

they often do in the movies okay now you

wouldn't really want a ten-pound brain

to begin with I'm told the women would

go on strike

I'm not giving birth to any babies gonna

have a 10 pound brain right and but

beyond that it would be mechanically

very difficult right you would twist

your head to see if anybody's about to

pass you on your bicycle and you would

just twist your head off which would

ruin your old day so 10-pound brakes I

don't know mechanically their problems

but maybe maybe you could do it but

that's what we assume but you know what

is it see if you have a 2-pound brain

you're a forest ape if you have a

three-pound brain you get you get tenure

here right it's only 1 pound difference

ok I don't know why shuts fine

alright here's here's an example this is

some guy who's thought about this I

forget his name even but yeah some

academic is thought about what we're

gonna look like so this is another way

into the question what et might look

like this is what you look like today

some of you this is what you might look

like 20,000 years from now you might say

there's not much difference but there is

some difference the eyes have gotten

bigger again foreheads have gotten

bigger because you know they're better

students and then 50,000 years from now

right nobody's black nobody's wide

everybody something in in between eyes

keep getting bigger

foreheads keep getting higher I got a

hundred thousand years now might as well

might as well invest in foster grants or

whatever they're gonna they're gonna

make money alright this is all it's fun

but I think it just misses the whole

mark it's all to anthropocentric it's

just again assuming everything out there

is going to be somewhat like us now we

like biology particularly beginning in

the eighth grade you like biology all

right but the troubles with biology in

terms of being a an intelligent being is

that a it's complex biology is very

complex it's hard to deal with right

it's because it's bottom-up engineering

you know you start with a single cell

that can kind of reproduce I go then you

build something else and then you build

more single cells and for you know

billions of years he build more

sales and eventually you build multiple

sell thingies it's bottom-up engineered

it's not designed it's not like the

college of engineering here right where

you design to I want I want a robot that

can do this you design it top-down you

don't make a very simple robot and they

just wait for it to evolve and it's

something because that'll be bad

engineering okay so and the proof of

this is that we barely work now I know

you don't think that but if you're

thirty or older you know that right

it barely work okay that's good biology

is okay but it's really complex

unnecessarily complex it's fragile and

you know it doesn't really improve very

quickly if you were to take Julius

Caesar's kids you know he had at least

one and throw them into Georgia Tech

they would do just fine I mean it first

thing to have to learn how to stop

writing in Latin or whatever but you

know this look okay but you know they're

no stupider than we are so in two

thousand years essentially nothing has

changed in terms of you know the the raw

material you can press that with Moore's

Law where if you have a laptop that's

more than four years old you're not

getting any respect at parties okay and

also of course biology has a short

lifetime I mean the whole model for

existence here on earth I don't want to

discourage you but if you think about it

you're right you know you're born for

six years you have some fun and then you

have to go to school and then for the

next twenty years you go to school and

maybe occasionally have some fun and

then you get out into the workplace and

you spend 40 years there probably not

having any fun and then you retire have

a little fun for 10 years and then they

throw the whole system into the ground

that's terrible right you don't want to

do that this is all the wrong model what

you want want is some other model now

here's the way to that other model

here's your brain your brain okay I

don't know why it says that but that's

interesting your brain nobody you know

nobody has a very good number for how

many flops your brain runs out you know

what's the speed of your brain in

computer terms but this is one estimate

thirty billion million instructions per

second all right most of you are sitting

here you know barely awake half asleep

and yet you're still running at 30

million mips right

if that's not efficient to begin with

not productive but he does you know

means your liver keeps working okay but

thirty minutes thirty million MIPS is

pretty impressive but there's already a

this computer in China right T on a two

I'm sure I'm mispronouncing it but you

know it runs at that rate now it's not

as compact as what's in your skull

admittedly but on the other hand it's

pretty general and doesn't require

coffee breaks

so we already can build a machine that

has the same processing power as your

brain okay

and you know about the applications this

is a fairly recent thing you know that

computers can beat anybody at chess now

they can beat anybody at poker now this

is the machine that beats anybody at

your poker here fortunately this has a

hard time belying up to the the 21

tables in Vegas because it could make a

lot of money but anyhow alright there's

that so this guy's out of work obviously

this is Kasparov Garry Kasparov back in

1996 when he lost to this IBM computer

in chess you can see what's not a happy

camper actually he said at the time it

was as if the computer had some sort of

alien intelligence well of course it

didn't it was just a game playing

computer was just following rules it was

very deterministic but what it proves is

that if you spend a lot of money you can

build a computer that can do a very

specific thing better than any human

right of course that's not what you want

you want to generalize artificial

intelligence yeah I can win a jeopardy

these are very good jeopardy players

here on either side that you can see

this guy in the middle is winning all

the money this guy in the middle being

an IBM computer also go goes a very

complex game more complex than the chess

and I think that this is I don't know

which one of these I guess it's this guy

I'm not sure which one of these guys is

the world champion go player but he

didn't win the computer beat him go is

gone all right so where's all this going

where it's going is shown in this plot

fight handsome or vich he's a robot

assists at Carnegie Mellon in lovely

Pittsburgh and what he did is plot up

how much compute power you can buy for

$1000 as a function at a time okay so

in 1900 the computer you could buy

$4,000 was fairly limited in capability

right but you know he keeps getting

better and his his pot stops in about

1997 the day to run out here now again

this is a semi-log plot so it's going up

exponentially

it's just Moore's law in 1997 for $1,000

you could buy a compute a computer that

had the processing power of a lizard I

don't that's interesting to you might be

if you're selling car insurance okay but

the point is that by 2020 I mean you

know these extrapolations are a little

uncertain but by 2020 your laptop will

have the compute power of a human right

this very little doubt about that that's

gonna happen now when I mentioned this

at the University of Washington years

ago some some students said well as soon

as you have a thinking laptop isn't it

going to kill us all and I thought okay

natural optimism of youth but but mine

was my rejoinder of this guy always

gonna say look you know I got some

goldfish at home and you know I am

smarter than those goldfish but I don't

wake up in the morning think I'm going

to kill those guys so I don't know I

mean I don't think it's dangerous at

first only because it may take your job

that's dangerous it may be socially

dangerous but it isn't that the

computers turn on us but the point is

this isn't far away you can believe this

or you cannot believe this I was at

Stanford actually a couple of years ago

for some TV program whatever it was and

the head of the AI department at

Stanford was in the room so in the

breaks between the shoot I went over to

him and he had his heads in his hands

and I I said so are we gonna have a

computer that can write the Great

American Novel by 2050 and he looked up

at me and he said yes and put his head

back in his hands

wait that was his analysis of of the

problem you can believe more you can

disbelieve him but if this happens 150

years from now 200 years from now it

doesn't matter it's all the same we are

inventing our successors in this century

okay now the point is that that leads to

this very simple timescale argument

here's you know 1900 they invent radio

suddenly these these people are

intelligent they could get in touch with

in half a cent

Gerard had computers this is during the

war but these computers had the same

architecture as computers new today less

than half a century right after after

Marconi and the the suggestion here is

that in another half century or another

50 years put it that way we may have

generalized artificial intelligence it's

unclear whether that will really happen

but if you do doubt it what if I said

okay maybe by 2150 would you dispute

that and I doubt that you would at some

point you say yeah it's gonna happen

unless you think there's a miracle going

on between your ears some of you do so

the point is if we defeat t us out there

it's not gonna be these guys right it's

gonna be this guy it's gonna be some

sort of synthetic intelligence and the

point is once you have synthetic

intelligence it can improve very very

rapidly all Darwin is so past say at

that point because Darwin did isn't

necessarily going anywhere it's slow but

the computer scan it's technology can

improve very very rapidly and that means

you ask the computers to design their

successors and they're not all going to

stay here now that's alien sociology if

you will or computer sociology but I

would think that the better computers

would just want to bolt a rocket engine

onto the back and go somewhere because

as interesting as George is they want

more energy they want more materials to

build maybe more circuitry so whatever

they do they can do it faster and this

is not where the action is the action

may be for example in the Centers of

galaxies big black holes right you can

get a lot of energy out of them so maybe

that's it yeah I mean this is you know

it's been good it's been a good run for

four billion years biology and it's not

that it's going to go away but it isn't

going to be calling the shots and the

point is this changes everything about

SETI because we keep looking for et on

some habitable planet somewhere we keep

looking at the list of exoplanets to say

well here's a good place

here's earth 2.0 they're at certain

point 2.0 but if this is correct if

there's any truth in this the real

intelligence in the cosmos is not soft

and squishy it's not like you it's some

sort of machine and so you know how can

we find something like that I don't know

I mean you've undoubtedly if I have

better ideas because they might not make

much

noise I mean I you know maybe they do

maybe they don't I don't know why they

would but there might not and that means

you might not pick up any signals the

only way to maybe investigate that is to

consider what was the sort of things

might they do what would interest a

thinking machine and I don't know but

here are some suggestions one they could

just play solitaire forever we're gonna

play solitaire until the universe dies I

mean I don't know is that interesting I

I think it's a future career for myself

it might be interesting but maybe the

machines would get bored with that maybe

they do these ancestor simulations this

is Nick Bostrom some of you may have

heard of him he's in the philosophy

department at Oxford he's written a

couple of interesting books and what he

says is look computer power keeps going

up it's going up exponentially so those

of you are familiar with simearth or

SimCity are all these you know

simulation programs know that they keep

getting better and better as the compute

power keeps getting better and what he's

saying what he said what he said about

15 years ago he said there's a 20%

chance that you're not actually sitting

here trying to stay awake and interact

with the person next to you this is all

a computer simulation 20% probability of

that now I interviewed him for our radio

show a Boston where'd you get this 20%

number and he needs to know you said

something but I still didn't understand

the second thing I said was well if this

is all a simulation do I have to live a

moral existence or can I just have fun

right and he's that stopped him for 10

seconds and then he said well maybe you

ought to live a moral existence I don't

know why he said that but he said anyhow

the point is that the really advanced

machines maybe this is all they do they

just relive the past I don't know if any

of you are doing yeah you're probably

not but and that's a suggestion maybe

they build stuff who knows they might

consider this problem this is one

problem that I can believe they might

consider this is the universe on a nice

day and it's destined for doom you know

that it's expanding it's not only

expanding it's accelerating everything

is getting farther and farther about

most things they're getting farther and

farther apart certainly over long

distance scales and as a result the

universe is going to keep on expanding

you get colder and colder and you know

how

billion years now that last star will

wink out right then eventually you know

maybe the protons decay that would be a

real bummer of a day or maybe I mean the

galaxies turned into giant black holes

and so forth all these sorts of things

that physics could predict and they're

all bad the stars are all gone I mean

and you know 10 to the 15th years it's

not gonna be enough energy to easily

collect in any place in the universe

where you could roast a marshmallow

now if the the real intelligence in the

universe are machines they see this

coming and they say what are we gonna do

about it because that's the end of the

fun so they might do something about it

they know I try and change the universe

this is an exercise left to the student

I leave you with this slide that I had

earlier today in which did this is just

an illustration of an idea by a guy at

Fermilab in Illinois Dan Hooper and he

says look this is obvious the aliens the

alien intelligence whatever they are

they're facing the final frontier then

the curtain finally drops and that's it

the universities it's getting colder and

colder you can do less and less and less

and consequently they're gonna try and

forestall that keep it at bay for at

least for a while by corralling all the

stars they can these big sources of

energy okay you might buy that you might

not they will raid nearby galaxies and

even galaxies and run so nearby and grab

as many stars as they can and bring them

back to where ever they are now I think

that there are technical problems with

that you know I could name some of them

but there are some obvious ones how you

do it where do you get the energy to

bring them back and in fact it seems to

me of just a simple calculation the

energy it takes to bring them back in

any reasonable and like the time is

comparable to the energy that they're

going to put out in their entire history

so I think their problems with this but

this guy's no dummy

he wrote an interesting paper about this

and he says you want to find where the

aliens are it just looks you just look

for a bunch of stars that have been

corralled by these really advances

intelligences this is stuff from science

fiction obviously but one should I think

I I don't know that this is right I

don't think it is but nonetheless it's

an attempt to get beyond the usual

thinking of what we're trying to find in

space and if we don't get beyond the

usual thinking I think that we're

restricting ourselves to a too small

sample space of what we might be able to

find so I'll just send it here what if

we find a signal most people think this

is what happens the audience the

audience the audience too but the public

riots in the streets because they can't

handle the news how many of you would

not be able to handle the news that we'd

found a signal coming from a thousand

light-years away okay five of you all

right now okay wait you just need to

chill of course you could handle news he

wouldn't say I'm not going to classes

today they found an alien signal

consequently I'm just gonna ride in the

street my kid I I just don't imagine

anybody's going to do that but that's

the general feeling out there in fact

this was a photo made in 1997 I think I

don't know if Paul steffie's is in the

audience he is Paul pointed out to me

this is all very misleading this is a

real photo I made this photo at 3:30 in

the morning at the SETI Institute

because we had found a signal that

looked like it was the real deal so

everybody was looking at what was coming

in on the computers now I thought that

this was the fault of a mechanical

failure at a radio telescope in Georgia

right but you know I I have blamed the

Georgians for this for years but Paul

points out to me that no that isn't it

they knew what this signal was and it's

just that the my colleagues didn't tell

me what they knew this this was actually

due to the so whole research satellite

European settlers so don't blame the

Georgians blame the Europeans that's

that's a better idea anyhow but here you

see people watching the screens I made

the this photo at 3:30 in the morning I

was very nervous about the possibility

this was a real signal and you know why

I was nervous I couldn't sit down that's

why I made these photos I was just

walking around with my camera taking

pictures for something to do I was

nervous because I had a dinner plan the

next evening and I had a luncheon then

following week and something I'm gonna

have to move all this stuff right you

might think that that's really nutty

which of course in retrospect it is but

at the time that's the kind of thing

you're worried about anyhow this turned

out not to be et but men and black did

not show up we thought it was men and

black did not show up

right the president didn't call the

mayor of Mountain View didn't call I

knew him he didn't call my mom didn't

call nobody called

until six hours after this photo was

made when the New York Times finally

called they'd already heard about it

okay so this is more likely what's going

to happen it's not something that

explodes the way it does in the movies

it's just a story that slowly uses out

into the media so I guess the the point

of this whole presentation is you know

we tend to extrapolate to the aliens

what we are and that's obviously not

necessarily a good idea okay you got to

stop here and maybe you have some

questions okay ready to take questions

just raise your hand and or shout them

out in Hungarian or something Hey

I was I was wondering why would you look

for intelligent life why would some

people look for intelligent life over

dumb life as you call it people look for

intelligent life in place of dumb life

there's a big advantage in looking for

intelligent as opposed to stupid life

anybody who's a member of fraternity may

know that the I don't know why I said

that but they didn't have fraternities

where I went this goes it's true that

microbial life is going to be much more

widespread than intelligent life under

any reasonable scenario I think that's

true unless of course you think that the

robots are everywhere which some people

do okay but I think the answer to your

question is it's some simply more

interesting wouldn't you find it more

interesting

in 1996 the biggest science news story

of 1996 was that Martian meteorite

alh84001 that was picked up in

Antarctica and there were scientists at

NASA and also at Stanford who claimed

that there were evidence there was

evidence of fossilized microbes in that

meteorite that meteorite came from Mars

that's for sure

we know it came from Mars as Chris McKay

of NASA says there was a brass plaque on

the bottom that had made on Mars so

that's for sure but the New York Times

which ran big headlines about this fine

had essentially no opinion pieces on it

they didn't get excited about it Stephen

Jay Gould at Harvard wrote an op-ed

piece and he said well it's kind of nice

but I would be more impressed by finding

intelligent life you're interested in

your peers you have a natural interest

in that you some down here to Margo so

yeah I already got the microphone so can

I ask the question okay yeah

dr. Shostak I wanted to ask you what is

your personal perspective on the Fermi

paradox what is my perspective on the

Fermi paradox it's paradoxical I don't

know if everybody knows the Fermi

paradox but it's very simple and Rico

Fermi some of you may have heard of the

guy apparently this may be apocryphal

but it seems that there's truth to it in

1950 he was having a lunch with a couple

of other physicist at Los Alamos and

between two bites of a tuna fish

sandwiches I said so where is everybody

okay

now what are you done has just made the

very simple calculation in his brain

probably took a microsecond for Fermi in

which he figured out how long would it

take to colonize the galaxy suppose

somebody gives you the job Ralph figure

out how we can colonize the galaxy right

okay it turns out you could do that in

maybe thirty million years 50 million

years 20 million years tens of millions

of years even with you know rockets that

are not all that fast

the real times you know the thing that

sets the time scales more how long you

have to let that column the develop

before it sends a rocket to some other

stars system okay but that's the order

of the time scale tens of millions of

years so say 10 to the seventh years but

the universe is right it's ten billion

years old if you if you will send to the

tenth years so it's a thousand times

older in the time required for this

little project so this is like all right

the Europeans discoveramerica if you

will right 1492 in within thirty years

within one generation there were

Spaniards all up and down the coast of

the Americas

so that

that took very little time once it got

started and that's the idea here that

you could colonize the entire galaxy

very quickly compared to the age of the

galaxy so if anybody was ever interested

in doing it they should have done it by

now okay so what's the what's the

prediction there you should be able to

look all around if I know there's a

colony there's a Kangaskhan and we look

out into space and all you find is

nature how disappointing you find nature

okay and so that's the Fermi paradox how

can you maintain that there's lots of

intelligence or even lots of life and we

don't say anything so how do you resolve

the paradox and you know you know you

there books written with solutions to

the Fermi paradox what I happen to like

that I may have mentioned earlier was

the urbanization hypothesis that the

galaxy is urbanized there's some places

which are much more popular than other

places and we happen to be in the

boonies here okay maybe but there are

other things so it's just too expensive

or the colonies never do much because

thinking you know Britain colonizes

Australia and 200 years later Australia

wants to be independent of Britain right

that kind of thing so maybe the colonies

that would go their own way and they

don't continue the project I mean there

are lots of explanations they're mostly

sociological the only ones that depend

on a little bit of science or

engineering are the ones that say work

out how much energy is required to

colonize the galaxy and ask yourself

wouldn't it be better develop a better

smartphone or something like that but it

has to apply to all the societies that

have ever sprung up in the galaxy

to be a good good response and nobody

knows if you come up with a solution let

me know what about another perspective

on the same problem dr. shorts thank you

we're talking about the Moore's law

before right how how the computing power

and basically information technologies

doubles each year and a half

wouldn't that lead advanced

civilizations to send radio waves or

just signals or use amounts of energy so

vast that in the end we will be able to

to detect them even if we all need to

look for them in narrow bands I'm not

quite sure I understand why would we not

be able to detect them to detect them

with radio telescopes that is why not

because the

because maybe there would be a meeting

radiation in many different spectra due

to the amount of activities they do the

amount of energy they consume etc well

I'm almost sure that I still didn't

understand your question I mean you

could you could argue that they don't

send signals into space for various

reasons they might not be interested in

the case of synthetic intelligence

it may have absolutely no motivation to

broadcast its its presence it may be

also the case that some people like to

say that it's dangerous to advertise

your presence there are people who very

much against us broadcasting anything

deliberately into space on the

assumption that way you don't want to

alert whatever's out there that we're

here you don't know that they're

friendly or whatever it is

I sound like like a president of ours I

that you know that that might be a

dangerous thing to do maybe it is but

that's alien sociology and all I can say

to that is that our data set for alien

sociology is sparse I said that nickel

okay so we don't know anything about

that and I don't I don't know that you

can draw any conclusions you mentioned

the James Webb Space Telescope and I was

just wondering is there anything in

particular that you would get really

really excited about if the telescope

found it when I use Oh is there anything

I would really get excited about if a

telescope found it James was a James

Webb Space a looker well obviously if

James Webb were to find some evidence of

biology elsewhere that would be exciting

it's not intelligent necessarily fact

the chances are it's not right just on

the basis of time scale we've had you

know life on the planet for four billion

years only three hundred thousand years

have we had almost a pians and only you

know seventy years have we had high

frequency high-power transmitters that

could communicate but if you did find

biology at least you would answer an

important question and that is if I give

you a million world sort of like the

earth what fraction of them ever cook up

life we don't know that

so that would at least tell you

something valuable that would say if you

find another one you know how things are

in astronomy they're on the only certain

numbers that are allowed for any given

phenomenon zero one two or infinity

that's

so if you find two you're well on your

way to infinity when you find three of

anything that's infinity why don't you

just ask it because I can all repeat it

yeah it's often squishy create the

machine intelligence I don't know how

are you I mean you could have machines

whoo yeah that's right

obviously the machines are created by

the soft and squishy intelligence just

like you're created by fish in some

sense right those are some of your

ancestors right the methane and oxygen I

put that into the story because most of

my colleagues would be upset if I didn't

talk about looking for life in the solar

system and that's where by the way

that's where all the interests and the

money goes because NASA is doing a lot

of that work there's hundreds of

millions of dollars being spent every

year by now so but also the European

Space Agency the Japanese Space Agency

the Chinese becoming interested there

there are a lot of people who are

interested in finding life in the solar

system right but the number of people

that are interested in finding

intelligent life well maybe you know the

public is but in terms of the research

community it's incredibly small any

given row in this room the number of

people sitting in that row exceeds the

total number of people in the world

whose job it is to look for intelligent

life very very small and that's that's a

money issue of course yeah do you do

have somebody with a microphone because

I can't yeah I got more here it's

probably a basic technical question and

I think this might touch on the question

I was asked over here right now work I

think we're confining our detection to

RF waves and I'm just curious I'm not

starting around I know how do we know

they're using RF waves is that like the

most efficient way to send a signal

through right you know X many galaxies

I'm sure there's some attenuation why

not x-ray infrared what are the so what

sort of like why why RF

yeah why are we looking for radio yeah

well partly that's historical to be

honest we invented radio before we

invented

Lazer's as an example otherwise we might

be just looking for lasered flashes and

in fact we do look for laser flights

there are experiments to do that but

they're not nearly as sophisticated as

the experiments to look for radio I

think that's because radio came on the

scene earlier but you know you could say

well what about something else and you

mentioned x-rays right neutrinos even

gravitational waves right then suggested

I talk to Pablo about gravitational

waves that's hard because you have to

slam neutron stars together or something

I got to make an easily detectable

gravitational wave and that's expensive

and how do you send I Love Lucy that way

anyhow you have to keep so radio does

have advantages centimeter wavelength

radio goes right through the gas and

dust between the stars that's a

consideration light visible light

doesn't do that so well so you have

certain limitations it could be

something other than centimeter wave

radio radiation Paul steffie's and here

we look for a millimeter wave but that's

still radio things like you mentioned

x-rays well x-rays may not be radio but

the thing is when you go to

high-frequency radio then again the

interstellar medium the gas that hangs

between the stars particularly the

ionized gas in that case will block it

it's like trying to you know get a

message through a curtain so you know

there are reasons to choose radio but

every week I get emails and people say

over radio so old-school

well that's true maybe it is but on the

other hand the wheel is kind of

old-school right and yet we continue to

use them and I daresay if Humanity is

you know sitting around a hundred

thousand years now there will still be

using the wheel right so there's some

things that have lasting value unless

you discover some physics somehow that

allows you to beat some of the

limitations of electromagnetic radiation

speed of light being the prime one over

here I don't know where here's reaching

okay how do you differentiate between

life and technology in your assertion

that our future is purely technological

and if we're looking for advanced

civilizations we're looking for the

technology where do you divide that

division between life and technology and

do you put a division there yeah is

there where's the division between life

and technology you should ask the

engineers

see if they have any life well I mean in

a sense all we're looking for is the

technology right but I mean the radio

transmitters don't build themselves yet

so the assumption is if there's a radio

transmitter then there's at least some

engineering capability behind that and

whether it's biological or whether it's

one of these machines that for some

reason needs to send information

somewhere else right then it's

still--it's intelligence and to say life

life is you know I mean you know what

life is it's just complex chemistry I

know most of you wake up in the morning

think well another day of complex

chemistry right that's what it is

maybe that's quite so disappointing okay

well but you know we don't care about

that we're just looking for a signal and

we know that this signal can't be

natural because of the characteristics

of the signal narrowband and all that

stuff so that means somebody built a

piece of machinery to make that signal

that's the first thing yes I think that

habitable zone is referring to places

where there might be liquid water

Enceladus is not in Earth's half I mean

in the solar system's habitable zone but

it's obviously a place that people would

look for life now because there is

liquid water due to I guess tidal

effects I guess my question is how how

how how much water liquid water do you

believe there is a Retton planets in the

universe and what percentage of those

with liquid water in your opinion have

life because all we have is a sample of

one for planets with liquid water with

life and that raises the question is it

common or is it extremely rare right

okay the first part of your question was

what's my estimate for the availability

there is in the universe in the visible

universe and you want the answer in

liters or gallons I mean okay well well

I would say is this I mean there's a lot

of it right that's it's not very

quantitative but three-quarters of the

universe by weight is hydrogen not

hydrogen if you're in the party balloon

business maybe because of the almost all

the remaining is he okay

three-quarters

waitis hydrogen and I think either the

third or the fifth most common element

in the universe is oxygen because stars

make some oxygen so you have hydrogen

lots of hydrogen and you have lots of

oxygen so the idea that there might be

lots of water is not at all radical if

you look at the outer of solar system

right these moons almost all these moons

have a lot of water content

I mean Enceladus alright obviously it

has a subsurface ocean but if you take

your rope up for example this is a moon

of Jupiter about the same size as our

own moon yes twice as much water as the

earth does and you might think the earth

has a lot of water right so water is not

a problem there's a lot of water and

maybe water isn't the only thing you

need I mean there you could go to Titan

you know next week and that's a moon

around Saturn it has lakes liquid lakes

but they're you know natural gas or

methane and ethane so it maybe you could

do it in some other liquid I mean nobody

knows but water it's not the problem

there's plenty of water and the only

reason we think water is essential is

because obviously it facilitates the

chemistry that that life is right those

have you old enough to remember

chemistry sets and you take all those

chemicals that in the chemistry set you

throw them on the carpet

now you antagonize your mom but not much

actually happens if you now wet it down

with the garden hose now things will

happen

so water is you know essential for the

chemistry it's at all I would say that

yeah the gentleman points out the fact

that we have a big moon and that may be

responsible for the fact that we have

such lovely biology on this planet and

humans and all that stuff because maybe

it stabilizes the spin axis of the earth

and it certainly does he should ask the

person sitting behind you

Gong ji here she does research on that

and she'll point out that Mars for

example has big swings in its orbital

tilt right and the earth without the

moon might have those two but did you

know might go to 40 degrees and it might

take how long is a couple of tens of

thousands of years for that to actually

happen for it to tilt over

and you know in 10,000 years even if

you're a snail you can get out of the

way right you can escape this problem it

isn't fatal isn't that tomorrow the

axial tilt you know brings Kansas to the

North Pole or something like that

you're still in Kansas but it isn't

Kansas anymore you know so I it's very

unclear that that would be a real you

know game killer if you will I mean it's

not maybe it's not good and besides you

know big moons yeah we don't know if

they're common or not but they might not

be terribly uncommon right a lot of

moons in the solar system they're

hundreds and hundreds of moons so inner

planets tend not to have them but still

you know you're talking about a trillion

planets in the Milky Way galaxy a

trillion that's a big number and sure

maybe most of them are worthwhile

worthless but if you were to buy a

trillion lottery tickets most of them

are worthless but you know trillion

tickets there are a lot of winners okay

let's let's take one more you know you

you guys actually have to go to class or

something I don't know Margo you decide

who's okay so if biological life creates

technological life or synthetic life do

you think there's a high probability

that biological life would have given it

a directive to make planets habitable

and thus it's still a good idea to

search for habitable planets see the

students have all the interesting

questions and also by the way the ones

that you can't possibly answer so would

with the the intelligent machines

receive instructions to turn other

planets into habitable planets I don't

know what what would be the incentive

right okay mr. robot we want you to go

out in this space find some planet and

terraforming it turn it into something

good I mean that would be like me going

out to the ants in my backyard okay you

ants you're really good at war I want

you to teach those ants on the other

side of town how to go to war I might do

that but I don't know why I do it so I

don't know I mean now you're trying to

guess what their motivations are likely

to be okay I'll be here for a while so

if you have any other questions

do one less oh right here so my question

regards us finding them um uh then I

mean in terms of life or them finding us

yeah some what happens soon and what

we're doing that's happened it's a good

question I mean you know what's likely

to happen first us finding them or them

finding us and there are plenty of

people who think they've already found

us as you know one-third of the American

public believes that the aliens are not

only out there but here right sailing

the skies in their saucers occasionally

hauling you out of your bedroom for an

experiment your mom wouldn't approve of

okay that would be that would be really

neat okay and I get calls every day from

people who are you know having troubles

with aliens and I wish one of them would

have some good evidence because that

would give me job security right I don't

think we're being visited and that

doesn't mean they haven't detected us

but how would the aliens find Homo

sapiens right there are very few ways to

do that you could say oh well they'll

just use really big telescopes and

they'll look for the freeway

interchanges right yeah maybe it takes a

really big you can work this out it's

you know freshman physics how big a

telescope it takes to be able to see a

freeway interchange from 100 light-years

that's hard it's not impossible but it's

hard really hard the easy way to find

you is to eavesdrop on the radar right

or the FM radio or the television that's

the easy way to do it but we've only

been sending that into space for 70

years since the war and that means

anybody more than 35 light-years away

hasn't had enough time for the signals

of you know there was early TV

broadcasters I'm or the radar from the

work to reach them and for them to

respond by saying we don't like Fred

Mertz his jokes on I Love Lucy and we're

going to invade your planet and

incinerate it or whatever you're gonna

do

so that means nobody farther than about

35 light-years hasn't had enough time to

find us and then come here and abduct

you for those breeding experiments that

wouldn't work it would be very

uncomfortable so III think that that's

such a small distance there's so few

stars within that distance might be a

thousand sergeant that I think it's

very unlikely that anybody out in space

knows about us yet I think the chances

are much greater that we'll find them

because we can pick up signals that were

emitted in a definite amount of time ago

okay

another

[Applause]