Ever wonder what would actually happen
if an alien civilisation made contact?
If they haven't already.
Would the public be made aware?
Or would it be kept secret?
How would we decode what they're saying?
And how on Earth will we reply?
Well, believe it or not,
there is an entire field of science
that is dedicated to this.
By sending intentional messages,
we'll let the civilisations know
that we want to make contact.
There actually is a protocol that tells us what to do
in case we pick up a signal that looks promising.
It's time to explore the unexplored.
Seth Shostak is a senior astronomer at SETI,
the rather cunningly named
Search for Extraterrestrial Intelligence Institute.
For decades, the institute has been leading the way
in actively searching for extraterrestrial signals
in the hopes of making the first contact with E.T..
Most people, when they think of looking
for intelligent life, they have some scenario
kind of like in Star Trek, right?
You get to a fancy rocket and you just, you know,
rocket off to some other world and look for it.
We simply can't do that.
But what you can do is maybe find the aliens at home
by eavesdropping on their radio waves,
or maybe they have flashing lasers.
If alien civilisations are anything like us,
then they'll emit plenty of signals all the time.
Radio, television, microwaves.
All we need to do is just eavesdrop
on one of these signals and then boom,
we've got contact.
To make this possible SETI uses 42 radio telescopes
called the Allen Telescope Array.
They direct these telescopes towards
clusters of stars that we know have exoplanets
in the hopes that one of those exoplanets
is broadcasting signals.
Now we're looking for signals that are
what are called electromagnetic signals,
which is to say, you know,
flashing lights or radio waves, I mean,
radio is just another form of light, if you will.
So that's what we're doing.
And why do we do that?
Well, we know that it would work.
We know that signals like that, like those could go,
you know, from one star system to another
and not become so weak that you could
never detect them.
I mean, it's always possible that
they've developed some new physics
that allows them to communicate in a way
quite different from what we're envisioning.
But you know, you can't do an experiment
based on science you don't yet know.
So we go with what we do know.
They haven't found anything definitive yet,
but what happens when we do?
A lot of people do think that
there's some sort of official procedure
if you find a signal. I mean,
wouldn't the Pentagon get involved and so forth?
Well, they've never shown much interest
in getting involved.
And asking for a procedure is like
asking Chris Columbus,
'Hey, Chris, look, you're going to get these three ships
and head west on the Atlantic.
What if you discover a new continent?
Have you got a protocol for that?'
Well, he didn't and it wouldn't have helped anyhow.
Are you as surprised as me to hear
that there is no official protocol
for when we receive alien signals?
Now people who are involved with SETI
tend to think ahead.
There actually is a protocol that tells us what to do
in case we pick up a signal that looks promising.
It's very trivial. It just says:
Check out this signal, tell everybody
and don't start broadcasting back
until you have the consent,
if you will, of the rest of the world's population.
So you don't have one society trying to monopolise
communication with the aliens.
What would happen after that is you would get
everybody in the world who can study this thing
because they got a big antenna or whatever.
Then they would build new equipment
that might be able to get the message.
In other words, the bits
that presumably are attached to that transmission,
and once you have those, now you have
the equivalent of the hieroglyphics
and now you try and figure out what they might mean.
Bear in mind, these might not be
intentional messages.
We could be picking up their equivalent
radio and TV transmissions that have just
stumbled into our radio telescope.
But for now, let's assume that they are sending
a direct message. What happens next?
What if we decide to talk back?
You know, how will we encode that?
Will we send them stuff in colloquial American English?
A language they always seem to understand
in the movies, or what else?
You know, probably it's better just to send
lots and lots of information.
I would just send them the internet myself.
Really? It's mostly video games,
TikTok dances, and ASMR.
Replying to any signal that we might pick up
is, actually it's very controversial.
You wouldn't think so, but it is.
You know, what are you going to say?
And there are some people say you shouldn't reply at all.
So the matter of replying is controversial
because of this potential for some sort of danger.
On the other hand, I'm sure
that if we were to pick up a signal
next week or next month or next year,
there are going to be plenty of people
who have the ability to construct
a transmitter and a backyard dish,
who are going to be sending their own messages
to the aliens.
That's more terrifying than sending
the entire internet.
But what's odd is if aliens exist
and there isn't some mass government conspiracy,
then why haven't we heard anything?
While as SETI continues their search
for extraterrestrial intelligence,
there's another organisation that thinks that
we shouldn't be waiting to hear from them,
we should be actively sending signals
to potential alien habitats.
What would you call an organisation
that messages extraterrestrial intelligence?
My name is Doug Vakoch,
I'm President of METI International.
For over 60 years, SETI scientists have been
searching for signals from other civilisations.
So far, we haven't found anything.
But what happens if every civilisation is doing
exactly the same as us?
It would be a very quiet universe.
That's why we should be sending messages of our own
to try to elicit first contact.
I'm at a scientific facility
far north of the Arctic Circle called EISCAT,
an organisation that sends radar signals into the sky
to understand the composition of our upper atmosphere.
But, the interesting part, the new angle, is that
we can also use it to send signals to nearby stars.
One of our prime targets is
the nearest star to Earth, Proxima Centauri,
which is orbited by a planet in the habitable zone.
We're sending signals that communicate
some core ideas of science, like chemistry,
the periodic table of elements,
something that we and the aliens have in common.
By sending intentional messages
we'll let the civilisations know
that we want to make contact,
and in some cases, that may just be
what's required to get a response.
Whether you think we should just wait and listen
or actively send messages out into the expanse of space,
the search is well and truly on.
We haven't yet found evidence of life
outside the Earth, let alone intelligent life.
But scientists do believe that there is life out there.
And remember, these signals can
take a really long time to transmit.
In the best case scenario,
we could send a message and get a reply
in just eight years.
That's how long it would take to communicate
with the nearest star to Earth.
More realistically, it could take centuries,
even millennia, to communicate.
So this is an inherently multigenerational project.
So there may well be another planet
a thousand light years away
whose messages are hurtling towards us,
and it could be any day now
that we finally hear from them.
Or maybe they're just watching and listening,
biding their time...
Or if they're anything like us at all,
they've been meaning to message us back
and they will, just after one more scroll.