All language subtitles for Royal.Institution.Christmas.Lectures.S2025E03.To.the.Stars.and.Beyond.1080p.iP.WEB-DL.AAC2.0.H.264-RAWR_track3_[eng]

On Christmas Day 2021, the largest
space telescope ever built

was launched into space.

This was the
James Webb Space Telescope.

It does amazing things.

It looks at the formation
of galaxies.

It looks at some of
the earliest stars

and also the planets
going around those stars.

But most crucially,
it's probably our best tool

for finding alien planets,

and possibly the aliens themselves.

So we're going
to continue our journey

from the Solar System,
through our galaxy

and out to the known universe

as we continue asking the question,

"Are we alone?"

Leaving Earth's orbit.

Houston, we have a problem.

Take third exit to Mars.

Mars rover collected.

Warning.

James Webb Telescope acquired.

Navigate off-road.

Voyager probe acquired.

Approaching light speed.

APPLAUSE

Welcome to the 200th anniversary of
the Christmas Lectures

from right here
in the Royal Institution,

supported by CGI.

Now, my name is
Dame Dr Maggie Aderin-Pocock,

and I'm a space scientist
and a science communicator.

Now, I've built instrumentation

that help us to better understand
the universe.

Now, going back to that
Christmas Day in 2021,

my daughter, who was then 11,
was opening her presents.

I was distracted.

All I wanted from Santa
was the safe launch

of the Webb Telescope into space -

a huge global project in which
I played a small part.

Now, the main feature of any
telescope is, of course, its mirror.

And of course,
the bigger the mirror,

the more light it can gather.

Now, this is the size of the
Hubble Space Telescope.

It is 2.4 metres in diameter.

You can see it's a lot
taller than me.

Now, Hubble sits in
low Earth orbit -

about 500km above sea level -

and from there, it's taken some
fantastic images of the universe

and transformed our knowledge.

But this...

..is the Webb Telescope,

and this is actual size -

18 segments all put together
to make this fantastic mirror.

Now, James Webb
is detecting infrared light,

and infrared radiation has
a much bigger wavelength.

But the challenge is this -

how do you get something this size,

along with a heat shield,
into space?

Well, to explain that, we use
origami and inspiration from nature.

So this is the
James Webb Space Telescope,

and as you can see,
it's unfurling here.

So there's the mirror.

This is the giant heat shield,

protecting it from radiation
from the Sun and Earth.

And what it's doing is deploying
all these mechanisms

so that it can be ready to detect
infrared light out there.

The final bit's the mirror
coming into place,

just as we've done here.

Thanks, guys.

Now, unlike Hubble,

Webb sits 1.5 million kilometres
away from Earth.

But why go to the trouble of
sending a telescope

out into space, so far away?

Well, Webb's location is needed

partly because it needs to be up
above the atmosphere.

The atmosphere absorbs
infrared light,

so we need to get it up above
the atmosphere

so Webb can do its work
detecting that light.

But my favourite thing about
James Webb

is the wonderful pictures it takes.

And here are my top three pictures.

Coming in at number three -
this is the first image,

and it's actually of
the planet Neptune.

But one of the things we can see is
one of the rings around Neptune.

Now, many people don't realise
but all the outer planets,

from Jupiter onwards,
they all have rings.

We know about Saturn's rings,

but we don't often see the rings
of the other planets.

But using this infrared light,
we suddenly see a familiar planet

but in a detail
that we're not used to.

OK. Coming in at number two -
it's this image.

Now, this image is looking
back through time.

So this is showing us sort of
ancient galaxies.

So, many of these galaxies
no longer exist,

but what we're seeing here is
a number of different stars,

and this is some of the earliest
galaxies that ever formed.

But my favourite picture is called
the Pillars of Creation.

Now, this was first photographed
back in the 1920s

by a scientist called John C Duncan,

and he used a black-and-white
photographic plate.

Now, the image we have here

is actually taken by the
Hubble Space Telescope.

But now, this is the Hubble image,

so we're looking at invisible light,

but let's fade that

into the James Webb
Space Telescope image,

and suddenly we're seeing
a lot more stars.

So, see, these stars are giving out
lots of infrared energy.

Also, I'm going to
come around this side

because these are the
Pillars of Creation.

And up here and here,
we've got these red areas,

and these are known
as stellar nurseries.

These are where new stars
are being born.

So that's the joy of it -

with the James Webb Space Telescope,

we're looking at our universe
but in a slightly different way.

So these images are
absolutely glorious,

but what if you could
transcend our atmosphere

and experience first-hand
that view from space,

just as Hubble and Webb do?

Now, to hear from someone
who has actually made that journey,

I would like to invite to the
theatre

the astronaut Tim Peake.

CHEERING AND APPLAUSE

Hello, Maggie. How are you?

- Hello, Maggie.
- Hello, Tim.

Now, what we've got
going on behind us,

- because it's nearly ten years
to the day...
- Yes.

- ..since you launched into space...
- Yes.

..and last time you did
a Christmas Lecture...

Because you've done one before!

But last time you did a
Christmas Lecture,

you actually did it from the
International Space Station.

- That's right.
- Is it good to be
here in the theatre now?

Oh, it's fantastic to actually
be back down on Earth.

But I have to say,
I did enjoy my time up in space,

and that was so exciting
to be able to come down in 2015

and join you from the
International Space Station.

Now, one of the things that I've
heard when I speak to astronauts

is that when you're living on
the International Space Station,

one of the places that people love
to go

is something called the Cupola.

- That's right.
- Yeah.
Now, can you explain what that is?

Absolutely. So this is the
International Space Station,

and this is the front of it.

So imagine that the Space Station
is flying towards us out the screen.

But if we rotate this 90 degrees,

we'll look down the length of
the Space Station.

And actually, this thing's about
the size of a football pitch,

so it's quite big.

But whenever you get
any free time at all,

all the astronauts,
we like to grab a camera

and go to this cupola window here.

- OK, so that's that nodule there.
- That's right.

If we turn it a bit more,
we'll see it a bit more clearly.

And the reason being is, as the
space station orbits the Earth,

we constantly pitch down like that.

- So this cupola window, it's always
facing planet Earth.
- Ooh!

And so when we go there,

you can fit your entire body
into that window, actually,

and just look down and see
the stunning view beneath you.

It's constantly changing,
by day, by night.

We never get bored.

And by the daytime, you just see
all of Earth's geology -

the deserts, the mountains,
the cloud formations,

the stunning colours
of planet Earth.

And then by night-time,
it's so easy to see that

we live on a planet of...
inhabited, you know,

people who've discovered electricity
because we see the cities,

the motorways, the lights
and everything.

And also, we see thunderstorms,
we see the aurora,

the Northern Lights,
the Southern Lights,

- and it's utterly magnificent.
- Oh, yes.

See, all my life I've wanted
to get out into space.

So just that description...
Just, whoa!

Do you think it changes
your perspective

to see the universe spread out
in front of you like that?

Oh, it completely changes
your perspective of our planet,

because you see it against the
vast black backdrop of space,

but also it changes your perspective
of, "Is there life out there?"

When you see that abundance of
stars in our galaxy,

it does make you think, you know,

there has to be life
out there somewhere.

So you're a believer,

you do believe there's
life out there?

I am a believer, yes.

I love it.
Optimism - that's what we need.

Thank you so much, Tim.

- And I think you'll be joining us
again later.
- Excellent.

- Thank you very much.
- So we'll see
you shortly.
- See you in a bit.

- Bye-bye.
- Thank you.

CHEERING AND APPLAUSE

So Tim went to the
International Space Station,

which sits about 500km
above sea level.

But on our hunt for alien life,

we're going to need to go
much, much, much further.

And so our new playground
is our home galaxy, the Milky Way.

So bring on the galaxy!

And here it is.

Our home galaxy, the Milky Way.

Now, we call it the Milky Way

but if we look back at other
cultures and back through time,

other people have called it
other names.

In the Kalahari Desert in Africa,

it was known as the
Backbone of the Night.

Now, the name Milky Way
actually stems from

a Greek legend which was about Hera,

a goddess who was breast-feeding
the infant Hercules.

And what happened is Hercules
came away from her breast

and the breast milk
spilt across the sky,

and they say that's what formed
the Milky Way galaxy.

But it is actually gorgeous.

And it is a collection of
many, many, many stars.

One of the questions is, where
are we in this Milky Way galaxy?

And I think I've got...
Thank you very much.

And I think I've got a little
"you are here" sign,

and that sits about here.

So we are in one of the spiral arms
of this amazing galaxy.

Now, how do we know that?

And one of the things is we believe
that the galaxy looks like this,

but we've never actually taken
an image of our whole galaxy.

That's because the
galaxy is so huge,

we can't travel far enough away
from it to take the whole picture.

But what we can do is
we can look out into space

and see other spiral galaxies,

and we're pretty convinced
that this is the view.

We are in one of the spiral arms
of our galaxy.

Now, humans have mapped the stars
for thousands of years -

from the ancient Babylonians,
who'd draw pictures,

to the last century where we were
using photographic plates.

But now we know more about
the galaxy than ever before,

thanks to a spacecraft called Gaia.

So Gaia has been out there
in space for 12 years now,

and it's created the most detailed
3D map of the Milky Way

that we've ever made before.

Now, to find out more about this

and discover
what Gaia has found out so far,

I'm thrilled to invite to the stage

my Sky At Night co-presenter

and galactic scientist,
Professor Chris Lintott.

CHEERING AND APPLAUSE

Hello! Hello!

How are you?

- Good crowd, good crowd.
- Good crowd!

Nice spaceship!

- Hey...!
- Careful!

CHUCKLING

This is great.

- You should stay here
all the time.
- I know!

- Actually... Yeah, this is my home
away from home now.
- Good, OK.

- Good, good.
- You can come on board
whenever you like.
- Fab.

Thanks, Maggie.

So tell us a bit more about Gaia.

First of all, how does it work?

Actually, sorry -
just to start with,

this is the Gaia spacecraft
sitting out there in space.

Yeah, so the magic thing
about Gaia is it's only

a small telescope,
but it does a really clever thing.

It measures the distance to stars,

and I can show you how it does that

with nothing more complicated
than your finger.

- OK.
- So if everyone in the audience
and everyone at home gets a finger,

and I want you to line it up with
something in the background,

and then I want you to shut one eye

and then switch to the other eye,

and you can go back and forth,

- and what you see is the finger jumps
from one side to the other.
- Yeah.

- So the background seems to change
quite radically.
- That's right.

Exactly. And then if you move
the finger further away,

so at arm's length,
and you do the same thing -

so one eye, then the other eye,
and then back -

what you see is that the finger
still moves but a bit less.

OK, lovely. OK, so let's go to
the ultimate distance.

I'm standing here on the stage,
and if you look at me

and then shut one eye,
and then the other eye,

you can see that the distance
is now quite small.

The background hardly seems
to move behind me.

So that means by
measuring that shift,

if you observe something
from two different positions,

you can get a distance,
and that's what Gaia does.

- Now, the trouble is, the stars
are a long way away.
- Yes.

So the shift is really small.

And so it uses not two eyes
but two sides of the Earth's orbit.

So it observes the same stars
six months apart,

and then we get the distance.

So we get a three-dimensional
map of the galaxy,

- but we can also measure
how the stars are moving.
- OK.

So we can see the velocity of
things as well.

Lovely. So that's it.

So Gaia has been out there
for 12 years.

So what's it been telling us?

Well, my favourite thing is
that we can predict the future.

- Ooh!
- So this is a map of the million
nearest stars in the Milky Way.

And we can show you
the next 1.6 million years.

- OK.
- So this is the future
of the night sky,

- because the galaxy is changing.
It's evolving.
- Oh!

So we think of the stars of the
night sky as static,

but this is projecting
into the future.

That's right,
and my favourite thing is,

- you can see these fast ones
that zip around.
- Yes, nip round.

They're popping in and out of the
pancake of the Milky Way.

- So they're rather special stars.
- Oh!

- But because we can do
this forwards...
- Yes.

- ..we can also go backwards.
- OK.

And so we can plot the past of
all the stars in the Milky Way,

and that's told us that our galaxy
is assembled violently.

- It eats other galaxies.
- What?!

And we see these streams of stars,

which are like the leftover dessert.

So they're remnants of galaxies
that our galaxy has consumed.

And they've got brilliant names,
these old galaxies that we've eaten.

There's one called the Kraken,
which is a sea monster.

My favourite is one called
the Gaia-Enceladus-Sausage,

which is just lovely.

- But there's something special that
happened 5 billion years ago.
- OK.

So this is the
Sagittarius Dwarf Galaxy.

- This is a simulation.
- So this is a cluster of stars.

Yeah, and 5 billion years ago,

or 6 billion years ago,
it came close to the Milky Way.

The Milky Way sparkles,

and this thing gets flung out.

It stretches out into
this beautiful stream.

And then, 2 billion years ago,
it comes close again.

And today we see it in the Gaia data

- as these long streams of stars.
- Yes.

But what's special is that...

- I said 5 or 6 billion
years ago.
- Yes.

Now, that's the time
that the Sun was forming,

and this encounter
with this tiny galaxy

may have kick-started a lot of
star formation in the galaxy

and it may be the reason
that we're here.

Our sun might have formed
in a burst of star formation

that was formed
by the Sagittarius Dwarf.

So that's the spark we saw earlier.

So what I want to ask you is,
in the current time,

how many stars do we think
are in our galaxy?

Gaia's looked at 2 billion stars.

- Right, yes.
- And that's a fraction of the whole.

So we think our galaxy
has got between

- about 100 billion...
- OK.
- ..and 400 billion.

- We're very bad at counting
the small ones...
- Yes.

..but let's say at least
100 billion stars

- and you won't go wrong
with that.
- OK. Lovely.

So I'm going to take as our
baseline 100 billion stars,

and that's in our galaxy,

and so that is a heck of
a lot of stars.

- It is.
- Thank you, Chris.
You're going to join us later,

but thank you so much
for joining me now.

See you soon. Thank you.

APPLAUSE

So we settled on
the number of around,

you know, give or take, 100 billion.

And so that is quite a
mind-boggling number.

But now what we're trying to do
is detect exoplanets,

planets going around the distant
stars we see in the night sky.

And of course, if they are
reflecting

the light from their local star,

we can barely make out the star -

how are we going to see
that reflected light?

So we need another way
of detecting exoplanets,

and we need to get clever.

So, first of all, I'd like to
introduce another method,

and we call it the wobble method,

and I think you'll see why.

And so, for this, I need to
call down a volunteer.

OK, perfect. I think, yes,
would you like to come up?

Yes, please.

I just love your hat.

APPLAUSE

So, first of all... Yes.

So, first of all, what's your name?

- Liam.
- Liam.
Thank you very much, Liam.

Now, what we're going to do
is we're going to try

and detect exoplanets.

But first of all, if you'd like to
stand in front of this star.

So what we have here is a star.

And it's a star, a distant star,

trillions of
kilometres away from us.

So we can't see the exoplanets
going around the stars,

but we can see the stars themselves.

Now, first of all,
we've got this star

and it hasn't got an
exoplanet around it.

Now, I don't know...
See how it's hooked there?

What I'm going to do is we're going
to give you a countdown,

and then - after three, two, one -
I want you to unhook it

and we're going to see
what happens to this star.

OK. So are we ready?

Three, two, one...

Ah, yes. You have to... Yes.

OK, so just like our star,

this star is spinning on its axis.

But as you can see, there's
not much movement there.

It seems to be spinning on its axis
and we're not getting much wobble.

So that is a standard star without
an exoplanet going around it.

But of course, we have exhibit two.

Now, this is a star

but now we have an exoplanet
in orbit around this star.

And what we want to do is compare
the movement of this star

with the movement of that star.

So, are we ready?

OK. So...

Three, two, one...

It's fiddly, but here it goes.

And so now, do you see
what's happening?

The star is wobbling and gyrating

because of the presence
of the exoplanet.

It makes it unstable

and so it sort of
moves around in this way.

And now, we can't see
the exoplanet from space,

but we can see the star wobbling
because we do see the stars.

And so this is
what we're looking for -

the wobbling of stars -

and that indicates that there might
be an exoplanet in orbit about it.

So, thank you. A round of applause
for our volunteer.

Thank you very much.

CHEERING AND APPLAUSE

So this seems like a great way
of detecting exoplanets,

but the problem is we can only
detect the larger exoplanets

and so we're talking about sort of
Jupiter-mass exoplanets

and in tight orbits
around their star.

But that's not really
what we're looking for.

We're looking for Earth-like planets
with sort of a broader orbit,

because they will sit
in the habitable zone.

And so we have another method,

and that's called
the transit method.

And funnily enough, we have
a demonstration for that, too.

So now, once again,
we have our star in the middle,

and now, I think, back here,
you might be able to see

we have an exoplanet in orbit.

And what I'm going to do, if I
press the right button..

OK. Our exoplanet is
orbiting around the star.

Now, imagine that we are
back here on planet Earth,

and we're looking up at this
exoplanet in space.

The star itself is giving out
a lot of light,

but what we have here is a meter
sitting on planet Earth.

OK, yeah, so we're just going
to dim all the lights.

And this is actually reading out
what this light meter is detecting.

So, at the moment,
it's about sort of 37, 38,

but when the exoplanet goes
between the star and us,

we should hopefully see
the light signal dip down.

So, there we go. Did you see it?

It went down to 15
and then it came back up again.

And so we can detect exoplanets
this way, using this transit method

as the exoplanet goes
in front of the star.

And this is actually closer to
the data we really get.

We actually have
what we call a light curve,

and it shows how the light changes
as the exoplanet goes in front.

So here it is.
So that's without the exoplanet.

That's the exoplanet going
in front of the star.

And then the light level goes back
up as it comes out the other end.

And so that is the transit method.

But using the transit method,

we can tell a lot about
what we're observing.

And so, as the exoplanet goes
in front of the star,

depending on how much starlight
is blocked out,

we can actually get an indication
of how big that exoplanet is,

how big its orbit is
around the star.

We can tell a lot of things about it

just by looking at this light curve.

And using this technique,

we have found many thousands
of exoplanets.

So, to date, we've got about
sort of 6,000 in the bag.

OK.

So, using the transit method,
one of the questions

we're trying to ask is,
"Are they habitable?"

And so how do we find that out?

Well, it turns out that the transit
method can help us with that, too.

And for this, we've got another
demonstration to show you.

It's all based on something
called spectroscopy,

because what we can do is actually,

as the starlight passes through
the atmosphere of an exoplanet,

it's a tiny, tiny fraction
of starlight,

but we can actually
look at that starlight

and analyse what elements are
in the atmosphere

of an exoplanet
trillions of kilometres away.

So what we're doing here is
mimicking

that transit method
that we discussed earlier.

So what we have here is
a bright source,

and that is representing
the local star

that the exoplanet is going around.

Then here, we have the
atmosphere of the exoplanet.

OK. Then, over here, what we're
doing is we're taking the light

from the star that's passing through
the exoplanet's atmosphere

and we're analysing it.

We're using this technique
called spectroscopy.

So let's dim the lights.

Let's set that atmosphere alight.

OK.

So now, here we have our
spectrum of colours.

So, as it passes through this piece
of equipment called a grating,

it is stretching the light out
into its component colours.

And we can see that
on the board here.

Now, Fergal, what you're going
to do is you're going to add

a compound to that atmosphere,
aren't you?

- Yep.
- And it's going to burn.

So what compound are you adding?

So this is sodium bicarbonate.

- Sodium bicarbonate.
- The same stuff
you would put in cakes.

Now, what happens is, as we add
that to the atmosphere,

some of the starlight will pass
through the atmosphere,

but with the sodium bicarbonate,

because it's a sodium-based
compound,

we will actually get absorption.

And so, as Fergal adds the
sodium bicarbonate,

we get a dark band.

Now, that is known
as an absorption band.

OK, yeah, I don't know
if you can see it just there.

And so, as you can see,
the flame is burning very yellow.

Sodium compounds sort of
absorb that yellow light,

and that's what we're seeing here -

the absorption of that sodium band.

So, thank you very much, Fergal.

So that's what's happening
in the atmosphere.

The starlight of the distant star,

it passes through the atmosphere
of the exoplanet,

and depending on what sort of
compounds are in that atmosphere,

some of the light will be absorbed,

and we can actually see that here.

And this is what we were seeing.

So I don't know if you noticed
the band was sort of in the yellow,

and so that's probably the yellow
sodium doublet there.

But other compounds sort of also
produce these absorption bands.

And so we've got sodium there,
we've got nitrogen.

Here's hydrogen.

And these are where the
absorption bands occur.

So when we look at an atmosphere,

we get a distinct fingerprint of
these absorption bands, and that

tells us the chemical composition
that that atmosphere has.

Now, remember, these are exoplanets

trillions of kilometres
away from us,

and yet we can actually do some
remote-controlled chemistry

and work out
what the composition is.

Thank you so much, guys.

Now, analysing the atmosphere
of exoplanets

can tell us whether
they might be habitable,

but can it actually
detect life itself?

Well, not exactly,
but it can give us an indicator.

There are certain molecules
that occur on exoplanets

and right here on planet Earth

that are what we call biosignatures.

Also, they're quite unstable,
so they break down quite quickly.

So when we see one of these
molecules in an exoplanet

far, far away, the question is,
have they been generated by life?

To find out more,
I'd like to introduce,

from the University of Cambridge,
Professor Nikku Madhusudhan.

CHEERING AND APPLAUSE

- Now, Madhu, if I may...
- Yes.
- Thank you.

Now, tell me about....

Because you made the headlines
earlier this year.

You made the headlines because of
a planet called K2-18b.

Now, this is an exoplanet,

and what you detected was,
I guess, a biomarker.

So can you tell me about this?

So this planet, K2-18b,
is about nine Earth masses in mass.

- So, quite big.
- It's quite a big planet,

and two-and-a-half times
the size of the Earth.

So, two years ago, we had already
made the first detections

of carbon-bearing molecules
in this planet -

methane and carbon dioxide.

So we think this is what is known
as a Hycean world,

it is the possibility, that it's

an ocean-covered surface with
a hydrogen-rich atmosphere,

and that it could be habitable.

- OK.
- In other words,
the conditions in the oceans

could be conducive for life.

So, already, two years ago, we saw
a tentative hint of this molecule

called dimethyl sulphide
in the atmosphere of this planet.

We weren't sure at that time,
but this year, what we published was

a second observation with
a different instrument,

- where we continue to see tentative
hints of this molecule.
- Oh, OK.

Now, DMS is interesting because it's

a molecule produced
primarily by life.

- Now, on Earth, this is,
I guess, plankton.
- Right.

OK, so these are
microscopic organisms

that live in the ocean,
and they produce the molecule DMS.

- That's right.
- And the fact that
we found this compound

on another planet,
it does seem incredibly exciting.

One of the questions we have asked
throughout time - "Are we alone?"

- And this is getting closer to
answering that.
- That's right.

The excitement here is that

even though we are
at the very early stage

and it's too early to claim
that we have detected life,

the fact that we are seeing
molecules like this

means we have the technology

to be able to detect biomarkers
in exoplanets.

This particular planet is hundreds
of trillions of miles away.

So the fact that we're able to
detect even a tentative hint

of such a planet from such
a distance is immense.

And that leaves the door open to

what else we can discover
on such planets.

Yes, and the fact that
these observations

are coming through the
James Webb Space Telescope.

This is the best piece of equipment
we have out there.

But of course, we have other things
in the planning,

and so maybe these sort of
detections

might be easier in the future.

Yeah. The search for life is
such a fundamental quest

that no amount of
observation time is going to

satisfy our curiosity to look for
what else is out there.

So, thank you very much, Madhu.

- But don't go yet.
If you'd like to step this way.
- Yes.

We have a little bit of fun
for you in the audience

because we've talked about

the possibility that
sort of life is out there,

but what would creatures
like that look like?

Would we just find biological
organisms or something very simple,

or what would alien life actually
look like out there?

And so what I want you to do
is join me in a game show,

and the game show is called

Draw That Alien!

OK.

Thank you very much.

CHEERING AND APPLAUSE

Thank you.

This is me getting into
game show host mode.

Now, first of all, I'd like to
invite Tim Peake back to the stage.

Come on down, Tim!

- CHEERING AND APPLAUSE
- Thank you very much.
- Thank you.

So, Madhu, please, you're going to
be part of the hosts for

Draw That Alien!

OK. So, first of all,
we are going to break up

this lecture theatre
into three parts.

You, middle section,
you are my section.

Tim, this is your section.

And Madhu, this is your section.

Now, what I'm going to do
for each section,

I'm going to give you
a real exoplanet,

and I'm going to tell you
the tentative information

that we have about
each of the exoplanets.

And so what I want you to do is,
when I describe this planet,

I want you to draw that alien! OK.

Now, let's start with my section.

Our planet is K2-18b.

Now, it's a water world.

So start drawing the alien.

What sort of alien do you think
might be on a water world?

Now, what do we know
about this planet?

Well, the information is
a little tenuous,

but we think its size

is somewhere between
Earth and Neptune.

So it's like a super-Earth

or sort of a Hycean planet,
as we mentioned.

It has an atmosphere, probably,
which is thick in hydrogen,

and it's mostly completely
covered in water,

and the average temperature
is probably about zero degrees.

Tim, were coming over
to your section. Perfect.

Now, you have TRAPPIST-1e,

- one of the planets of the
TRAPPIST system.
- Yeah.

OK. Now, TRAPPIST-1e
is a rocky planet.

And let me give you a bit more
information about this.

Now, its size is quite
similar to Earth,

so this is looking quite promising.

- It sits in the habitable zone
of its stars.
- Excellent.

But unfortunately,
it has a violent star.

This means extreme radiation.

OK. Madhu, over to your section.

Now, your planet is LHS 1140 b.

Now, this is an ice planet.

Now, this is called a super-Earth

because its diameter is about
two times the size of Earth.

We think it's got an icy surface,

but it is very, very windy.

But it has a light, puffy
atmosphere,

mainly made out of
hydrogen and helium.

Now, in the meantime, I'm going
to come and see my section.

So I'm coming up here.

So, how are your pictures
coming along?

What have we got?

OK. Lovely. I can see...

Ooh, gosh!

I can see a lot of artistic
interpretation here.

Now, what I need to do is select...

So can you hold them up
so I can see them?

Fantastic. Ooh!

OK. Oh, my goodness!

I've got to choose one
as an example to bring down.

Ooh, my! Ooh!

Actually, I quite like that one.

Yes, with the two googly eyes.

Thank you. Can you pass that up?

Thank you very much. Very artistic.

Fantastic. Thank you.

So, in a minute,
I'm going to cause a halt,

but I'm going to take this one down.

Tim, how are you doing?

- We're doing great over here.
- OK.
- Thanks, Maggie.

- Yeah.
- I think your time is almost
up. Select your alien

- and bring it on down.
- OK.

Yeah. Let's go for this one.

There we go. Thank you very much.

Madhu, how is your section doing?

- Lots of choices here.
- Lots of choices.

LAUGHTER

I know. It is very hard.

- My apologies.
- Very, very, creative.

Yeah, that one. Yeah.

OK, yeah. Pass it along, please.
Thank you.

So, guys, thank you so much

for participating
in Draw That Alien!

OK. Let's look at the results.

- OK.
- So, Tim, I think
we'll start with you.

- Right. Are we ready?
- Show me the alien on your planet.

TRAPPIST-1e.

Here we go. There we are.

We've got an alien that clearly has

to protect itself from radiation.

- Yes.
- So it's already developed

this complex life form
that has shelter.

OK, yes. Built-in umbrella.

Has the ability to walk on
the rocky planet, obviously,

and support its own body weight
on that planet as well.

- Fantastic.
- So there we have it,
TRAPPIST-1e.
- So there we have it.

Yes, that is the alien.

And Madhu, what do you have?

So we have a simple
tardigrade-like planet.

You want to go simple
on this planet.

- We didn't want to make
too many guesses...
- OK.

..too much complexity.

- So I'm happy with that, yeah.
- So you've gone... Yeah...

- Simple life form on an
ice-covered planet.
- Yes.

OK, perfect. And water.

And we've heard that tardigrades
can survive sort of very extreme...

Harsh conditions, yes.

OK. And this is what
I got from my group.

Let's get it the right way.

Very good, I think, artistics here.

And I'm going to put that in.

And what do we have here?

So we have a sort of bulbous alien
with a number of tentacles.

I love the eyes.

And the eyes are quite spread out,

and so it gives it sort of
a good viewpoint.

So I think those
are wonderful examples

of alien life on other planets.

So I think a round of applause
for everybody who drew an alien.

APPLAUSE

But first of all, I wanted to say

that now each of you is
an astrobiologist,

because astrobiology is the
science of trying to work out

what kind of alien life you'd
find on these exoplanets.

So pat yourselves on the back.

You're astrobiologists now.

But now, this is the bit
I've been waiting for most

because I think, Tim, you,
and you, Madhu,

have drawn your own alien, and
I must admit, I've drawn mine, too.

- So, Tim...
- OK.

..let's put these down,

and could you get out
the alien you drew?

So this is an alien
living on your planet.

Yes, yeah. So this was
my alien on TRAPPIST-1e

that I drew earlier.

Fantastic.
Madhu, what have you got?

So this was actually drawn
by you, wasn't it?

We tried!

HE LAUGHS

- So do you want to put it
in the stand?
- Er, yeah.

With all the courage I can muster.

Actually, this is your worst
nightmare, wasn't it?

- Happy as scientists!
- It was indeed.

Science is the easy part.

THEY LAUGH

Maggie, did you draw one?

Oh, me? Well, actually,
I didn't have much time.

- Right.
- So I just threw
something together.

- Oh, OK.
- But I've just got it here.

And, um, yeah, so it's a bit rough.

- So, yeah, apologies.
- Oh!

- Yeah.
- Oh, right.
- Right, right.

This is just something
I threw together.

Not much time.
Let's just put that there.

OK. So if we were going to vote,
I wonder whose would be best.

Did you really...?
Did you draw that?

I think that's enough of that!

Thank you so much for participating.

I think that's enough of
Draw That Alien!

APPLAUSE

Thank you.

I'd better not be a
game show host any more!

So, thank you both, guys.

- Thank you very much.
- And I think
I'll be seeing you again later.

- Thank you.
- Thank you.
- Thank you.

So we've been talking about
the search for alien life out there,

looking at what compounds
might be found in an atmosphere

of an exoplanet far, far away.

But what if we wanted to actually
go out and find these aliens?

Now, our nearest exoplanet
is Proxima b,

and it's actually a rocky world,

and it's about sort of
4.2 light years away from Earth.

Now, that sounds like
it's worth a visit,

but just how far away is that?

So a light year is actually
the distance

that light will travel in one year.

And that turns out to be

9.5 trillion kilometres.

So that's 9.5
with 11 zeros after it.

So, there it is.

So the distance to our
next-door neighbour star

is 40 trillion kilometres.

So what if we wanted
to travel there?

Until recently, the fastest
we could travel in space

was about 1,600 metres per second.

It's nowhere near
the speed of light,

but it's still pretty quick.

Now, if we could travel
at that speed,

and travel out towards
Proxima Centauri,

that journey would actually take

76,000 years.

And that's just going from our star
to the next-door neighbour star.

So what we need is
a faster way to travel.

Now, there's actually a project
going on right at the moment,

and it's called
Breakthrough Starshot.

Now, instead of carrying heavy fuel
on board the spacecraft,

what they need to do is
make it light and agile.

What we do is we use
a massive solar sail.

Now, I've got a little demonstration
to show you how this works.

Fantastic. Aha! I have the water.

Fantastic. Thank you.

So what I'm going to do is
I'm going to pour some water

in here, without making a mess.

Whee!

And then what we're going to do
is add our boat.

There's the water,
and there's our boat.

OK. Now, we've actually used
this technology,

and in the past we've
used light from the Sun

to accelerate things through space.

But what we want to do now is,
we don't want to just use light,

we want to generate our own light.

We want to use lasers.

What we're doing is
we're distributing balls

throughout this section.

Now, each one of these balls
represents a photon of light.

So this is laser light.

So what we need is a sail,

and so what we're going to do
is get a solar sail.

Bring on the solar sail!

And here it is.

So this is our solar sail.

And what you'll see is it's made out
of very, very light plastic.

So now what we have here
is our solar sail.

Now, remember, what we have
here in the audience -

each one of these balls
represents a photon of light.

And now I want you to throw them
towards the solar sail.

So...

First of all, I'm getting
out of the way. OK.

And so what I want to do is
I want to count three, two, one,

and throw them at the solar sail.

- So, are you ready?
- Yeah!

Three, two, one...

Throw your photons!

OK!

OK. So your photons
hit the solar sail.

OK. We've still got
incoming photons.

I thought this would be a problem!

But, yeah, apart from
getting bogged down,

look, our solar sail
has made its way,

all the way across,
out beyond our solar system

to the other end of the trough.

And so this is the plan
for Breakthrough Starshot.

Up here, I've got a picture of
a real solar sail.

So this is what we're designing.

This is the solar sail,

and you can see it is very much like
this sheet of metallised plastic,

but it sits in space
and it is absolutely ginormous.

Now, as I said, in the past

we've used light from the Sun
to accelerate them,

but what we need to do now is use
these photons of light, this laser.

So we will send a pulse
of laser light into space.

Now, you only need
a pulse of laser light,

because once you accelerate
the solar sail,

because we're in
the vacuum of space,

there's nothing to slow it down.

So you accelerate the solar sail,

and we have very tight
pointing accuracy,

and we point it towards Proxima b.

Now, we can actually set this up and
we can point it towards Proxima b,

but we have no means
of slowing it down.

So, as it approaches
Proxima b, it will fly past,

but what we want it to do
is take photographs.

So, as it flies past Proxima b,

it will take photographs of
that exoplanet

and it will bring those photographs
back to Earth at the speed of light.

So, even then,
it will take 4.24 years

to get those images back.

But if we do this, we might be able
to get closer to the answer of,

"Are we alone in the universe?"

But there's a few things to say.

If we can get this
technology to work,

then we can actually accelerate
this solar sail

to about a fifth of
the speed of light.

Now, I'm a Trekkie,
so that's warp factor a quarter.

But the probe we can send can
weigh no more than one gram,

because if it's any heavier,
it has inertia,

and so then we'll need
more energy to accelerate it.

If we actually get up to
a fifth of the speed of light,

that journey of
40 trillion kilometres,

it won't take 76,000 years.

We'll be able to do it
in just 20 years.

Thank you very much. And a round of
applause for our volunteers.

CHEERING AND APPLAUSE

So, with a solar sail, we can get
something very small and lightweight

out to an exoplanet
and take photographs

and bring them back to Earth.

But my dream has always been
literally to travel to the stars.

So what if we wanted to get
something a bit more massive,

something like me, out to the stars?

Well, there is also a new way
of thinking about it.

We're talking about the
Alcubierre drive.

And this is a theoretical way of
travelling into space,

and it's been developed by
Miguel Alcubierre,

a Mexican physicist,

and what he's suggesting is
that we actually...

Well, we manipulate space
and time itself

to travel out into space.

So, now, for this,
I'm going to need another volunteer.

I always hate doing this. OK.

Actually, would you like to come up?

A round of applause
for our volunteer.

APPLAUSE

Thank you for joining me.

Now, first of all, what's your name?

- Bukayo.
- Bukayo.
- Yeah.

Very nice to meet you.

Now, what we've got here is
my Alcubierre drive.

Now, if you can put your feet
just on the edge there.

This is planet Earth,

and at the other end of the carpet
is Proxima b.

Now, this carpet represents
space and time.

And that's something
that Einstein came up with -

the idea that we can take
three-dimensional space and time

and smoosh them together.

So this is the space-time carpet.

And out there, yes,
that is Proxima b,

and we want you to travel there.

Now, first of all,
what I want you to do

is just take one step
and get to Proxima b.

So give it a go.

Yeah, that's... Whoa!

SHE LAUGHS

That's big, but not big enough!

OK. So do you
want to come back here?

Thank you very much. I'm just going
to sort of straighten up

space and time. Just even that out.

OK. So, now, travelling
conventionally,

it will take quite a while,
as we've worked out,

to get to Proxima b.

But what if we can actually
manipulate space and time?

So what we're going to do
is we're going to

scrunch up space and time
in front of you.

So this is the principle behind
the Alcubierre drive.

Rather than trying to take
that big leap,

what we do is we concertina up,

or scrunch up space and time.

So, now, when you take your step,

it's quite easy.

So, because we've manipulated
space and time, scrunched it all up,

we have effectively brought
Proxima b towards you.

But that's not all we do,

because we've scrunched space
and time up in front of you,

but what we need to do now
is elongate it behind you.

So, now, this is it.
With the Alcubierre drive,

we scrunch it up before you

and we elongate it out behind you.

So there we have it.

You have travelled from Earth
to Proxima b in just one leap.

So a round of applause
for our volunteer, please.

Thank you.

APPLAUSE

So this is something that's been
worked out mathematically.

Mathematically, the
Alcubierre drive seems to be

a feasible way to travel
in the future.

But there are a few caveats.

One of the things is,
actually, to scrunch up

space and time like that
and elongate it behind you,

you need huge amounts of energy.

And that energy, we just don't have
access to at the moment.

But maybe in the future, we'll find
ways of making that energy

and we'll be able to travel
these vast distances in space.

Let's assume that we've made it
to another planet

and there is some
kind of life out there.

But what are the chances of finding
civilised life, intelligent life?

And what is the probability
of just finding bacterial slime

or something a little
more sophisticated?

Well, to make this discussion,

I'm going to call back
Professor Chris Lintott.

APPLAUSE

Now, back in 1961, Frank Drake
came up with an equation,

and it was trying to work out
the probability of finding

civilised life - and we'll
define that in a minute -

within our galaxy.

Now, for this,
we've got seven volunteers,

but I think they've already
been pre-selected,

and so would our seven
volunteers please stand up?

And will you all get out your
whiteboards, please, and your pens?

Now, also, each of the volunteers
here in this line represents

a parameter from the Drake equation.

So this is the Drake equation here.

Yeah, so this is how you
calculate...

We're not going to think
about probabilities,

we're going to try and calculate
the number of alien civilisations

in the Milky Way galaxy that
are there right now

- for us to talk to.
- OK.
- So, when we're looking for

alien life in the galaxy,
this is what we need to know.

- Are we going to stumble across
aliens wherever we look...
- Yes...

..or is it going to be really
rare and difficult?

- So, that's what this equation
calculates for us.
- OK.

Drake developed this equation
back in 1961,

and then, some of the parameters
weren't known.

But what we're going to do is
actually go through each parameter

and write down what you think.

Now, Chris, I hate to say this,
but you're a bit of a Grinch,

- aren't you?
- I am at this, yeah.

I think... I'm going to be
a pessimist today, I think.

So let's see what the odds are,
even if we think we might be

a little lonely in the galaxy.

- OK.
- But we know the first few terms,
though, so we can start with

the number of stars
in the Milky Way,

- and we know that from Gaia.
- We spoke about that earlier.

So we think there are
100 billion stars in our galaxy.

So, please, for the first term -
so, you are N* -

could you write down
"100 billion"?

- So, that's 100 with nine
zeros behind.
- That's right.

- OK.
- Yeah, and we know
that pretty accurately,

at least for astronomers,

there might be a factor of two
in there or something.

- Yes, but ballpark, ballpark.
- Yeah, exactly.

And that's what this is about, OK.
So, let's go on to the next.

So, what's the next term?

- So the next one is, how many of
those stars have planets?
- OK.

And when I was growing up watching
the Christmas Lectures,

- we didn't know that at all.
- Yes.
- But we now do.

We know that the Milky Way
likes making planets.

So, we can more or less assume
that every star has a system

of planets going around it.

So, this is function FP.

Yes, so it's the fraction of
stars that have planets.

- We're going to say one.
- OK.
- All of them do, more of less.

OK, so, yes, some might have more,
some might have less.

So, could you put one
on your scoreboard?

Thank you very much. Thank you.

OK, so what's our next priority?
We've got NE.

Yeah, so this is the number of
those planets that are capable

- of supporting life.
- OK.

So we could argue about
what you need to support life,

but maybe we think our kind of life.

So you need water,
maybe a rocky planet.

Well, these are quite common,
we've found out recently.

So we know Earth-like
planets are common,

so we might as well
put one here, as well.

So I reckon every star
that has planets, on average,

will have one planet capable
of supporting life.

So that's a one, as well.

- OK, but now we're going into
what we don't know.
- Yeah.

We're going from the modern
science to future science.

So the next thing we need
to know is this FL.

- So if we've got a planet that
can support life, does it?
- Yes.

- OK.
- What fraction of planets
have life?

And here, this is
where my pessimism,

my Grinch-like tendency comes in.

So I think we haven't found life
anywhere but Earth yet,

- and we've been looking.
- Yes.

So I reckon life must be
pretty rare, so -

this is a guess - let's say
one in 1,000 of those planets.

- So, one in 1,000.
- Yeah.

So, can you write that
on your screen?

- One divided by 1,000.
- Then the next term...
- FI.

Yeah, so that's the fraction of
those planets that have life

where you get intelligence.

Yes, OK, so intelligent life.

Yeah. Now, again, there's just us.

- If we're...
- But are we intelligent?

Well, we're as good as it gets,
Maggie, as far as we know,

you and I,
and this wonderful audience.

And I think... You have to think,
it's taken five billion years

of the Earth to get to here,
and we've only just made it.

- So I reckon intelligence
must be rare, as well.
- Ooh, OK.

So I'm going to say one in 1,000 -
one divided by 1,000

- for this, as well.
- OK, can we put that on the...?

On the case already, this is good.

Lovely. And can you hold it up when
you've written it out? Thank you.

OK, so, now, what's the next thing?

Well, this is FC.

- So this is the fraction of planets
that have intelligent life...
- OK.

..that are capable of,
and willing to talk to us.

- Oh, OK.
- So, one way of thinking
about this is maybe,

do they have radio?

- Have they developed radio?
- Ah!

- So, for example, if you think about
the Aztecs or the Romans...
- Yes.

..past civilisations,
they were intelligent

- but they wouldn't be in this
category.
- Yes, and so it's the

- technological capability to actually
communicate.
- Exactly.

So I'm going to use my recent
argument again -

we've only just, in the last
maybe 100 years, started to do this.

I reckon it's going to be rare.

- Let's...let's say one in 1,000
again.
- OK, one in 1,000. Thank you.

- Let's get that...
- I want to
point out, I could be more grumpy

about all of these, as well.

One in 1,000 I think
is quite generous,

so hopefully, we'll get some
aliens at the end.

OK, so that's one over
1,000 again, OK.

And then we're coming to
the last term, FL.

Yeah, this is the most unknown term.

- So this is how long you last
as a civilisation.
- Oh, yes.

So... Well, we've got
at least 100 years,

because we've been transmitting
radio waves for about 100 years.

So maybe I'll be generous -
let's say we'll last

- at least twice as long.
- OK.

So, 200 years for the lifetime
of our civilisation.

But the Earth will exist for about
ten billion years in total.

- OK, cos we're about halfway
through the life, OK.
- Yes.

So that's 200 divided
by ten billion.

- Oh, OK.
- So, that's a
really small number.

So can you write 200,
and then divide by ten billion?

- So we get more ignorant
as we go along...
- OK, yes.

..but we can guess all
these numbers,

and then we can put them together
and calculate the number of

civilisations there are
for us to talk to.

- So, let's do just that.
- OK.

- Can you send all your sheets to this
end?
- Shall I go and get them?

Yeah, and Chris, if you can
go and get them.

So, if you pass them up, what we're
going to do is put them into

the Drake Equation calculator.

Oh, is that what that thing is?

- Yeah!
- OK, good.

MAGGIE LAUGHS

- Was it expensive, Maggie?
- Incredibly.

- OK.
- We blew our budget on this,
but I think it's worth it.

Excellent. And we're not going
to ask how this works.

MACHINE BEEPS

- Ooh.
- I know!

SHE GIGGLES

So, OK, I think we're ready.

I'm going to press the red button,
and we'll get an answer.

I'm going to stand back.

- OK, so, three, two, one!
- ..two, one!

Let's see if we can get an answer.

- Whoa! OK, that's not good.
- Is it supposed to do that?

- Yes.
- OK!
- That's what I'm going
to go with, yes.
- All right!

- Oh, hang on!
- Oh, it's doing its calculation.

CHRIS LAUGHS

Ooh, OK!

- So we have a scroll, and let's see
what's on here.
- Of course we do!

- Fantastic.
- So, this will be...
- Ooh, more smoke!

..our calculation of the number
of civilisations in the galaxy

- that we can talk to.
- OK, so let's
get this the right way round.

OK. So, Chris, if you hold
the other end...

- So, the number is...
- OK, so it's less than one.

We've got...

- It's not very many.
- It's not very many at all!

Do you think you might have been
a little over-pessimistic here?

Well, I think I was quite generous,
actually, all those 1,000s.

But this is the point,
so in this situation,

if we're right about those numbers,
we're it!

We're almost certainly the only
civilisation in the galaxy.

You could multiply this
by a million,

and there'd still only be
two civilisations.

So, yes, so if you took every star
in our galaxy and multiplied it

by a million times,

there'd only be two civilisations
in our galaxy -

so us and someone else to speak to.

And, of course,
they could be far, far away,

so we can't actually communicate.

So, if you believe the numbers
that we put in,

then you have a world, a galaxy
in which civilisations appear

and then disappear pretty quickly
and they never talk to each other.

- Yes.
- It's very festive!
- Well, not very festive at all!

- I feel quite depressed!
- No.
- I think I would be really...

I don't want to be alone,
and that makes me feel very,

- very lonely, Chris!
- No, I should say,

even if this is true,
we should look anyway,

- because you never know.
- OK! Yes.

Because there were things in there
that we didn't understand.

- But, of course, you can also
change the numbers...
- Yes!

- ..and think differently
about things.
- Lovely.

So, Chris, if you'd like
to step over here,

what I want to do is, I want
a slightly more optimistic approach.

Now, when I think of optimism,

I think of someone who's
travelled out there into space.

Tim, would you mind
coming down again?

- A round of applause for Tim!
- Hello, Maggie. Hi.

APPLAUSE

- Good to see you again, Tim.
- You, too.

Now, that answer was
a little depressing to me.

A LITTLE depressing? God!
Only 100 years left to go!

- Goodness me!
- Wipe-out, yes.

So, Tim, what I'd like you to do
is offer some alternative numbers.

- Right.
- OK, first of all, so you've
got 100 billion...
- OK. 100 billion.

- Yes, and then it was one and one.
- One and one.
- OK.

So, if you put those on your
boards and hold them up.

So 100 billion takes
a little longer to write.

And that gets us to the fraction of
planets that could support life.

- Yes.
- OK.
- So we agree on that.
- We're on FL.
- Yeah.

And I actually think
the raw materials are abundant

in the universe for life.

- Water and ice is everywhere,
organic compounds.
- Yes.

And on planet Earth, as soon
as the conditions became

favourable for life, life evolved.

- And so I'm going to go
for one for FL.
- OK.

So, if life can exist on
a planet, it will.

- That's what you're effectively
saying.
- Absolutely.
- So, perfect.

Let's put a one there on the board,
and let's hold it up, please.

- OK, so we've got one.
- Right.

OK, so go on to
the next parameter now.

So, FI - intelligent life.

And I do understand Chris's
point of view here,

but, given enough time,
I think life finds a way.

It's always going in one direction.

- It's evolving!
- And that's
becoming more complex, evolving.

- Yes. So what are we going to put
on this?
- I'm going one.

- I'm all in.
- OK, one, OK.
I love the optimism!

- OK.
- Right, FC.
- FC, yes.

Will that intelligent
life communicate?

Again, I'm taking the positive
view that intelligent life,

at some point, will ask
itself the question,

"Am I alone in the universe?"

and "I'm going to try and
communicate with other intelligent

"species out there" - so that,
for me, is a definite one.

OK, perfect. Lovely, so let's
put one on the board

- and turn it around.
- I suppose
we exist and we've done it,

- so I guess there's a logic there.
- We're not that intelligent, so, yes!

THEY LAUGH

- OK, so, then, the last one.
- FL.

- Yes.
- So I'm going to take Chris's
rather depressing 100 years...

- Oh, yes!
- ..and say, actually,
as a species and intelligence,

you know, it solves problems,

and our technology
is getting better and better,

our life expectancy is improving.

- Yes.
- We're able to overcome problems.

- Yes.
- Our medicine is getting
better and better.

There's every indication and
every potential that

if we collaborate and work together,

we'll last as long as this
planet can maintain us here.

Which is about 4.5 billion years
into the future. I like this.

Absolutely, and so
that will be half of the entire

- Solar System's life.
- Yes, perfect.

- So we're going to have to put
0.5 for our final one.
- OK, 0.5.

So what we need to do is gather
these results up and put them in

- the Drake Equation calculator.
- OK.

- Thank you, if you can bring
these down.
- All right,

- can I have these ones, please?
- This is a lot more positive.

- Maggie, I'm going to stand
over here.
- OK.
- Thank you.

I'm going to let you and the
astronaut be next to that thing.

THEY LAUGH

I do my science at a computer,
I don't use those things.

- Yes, the smoke was a bit worrying,
that's all I can say.
- Yeah.

- It's perfectly safe!
- All right,
Maggie.
- Fantastic.
- Here's the

- more optimistic version.
- Fantastic.
Now, let's put this in,

put them all together.

Let's slot them in. Thank you.
MACHINE BEEPS

OK, we are getting the calculation.

So, let's hit the red button.

So, let's count down.

Three! Two! One!

What's the answer?

Ooh, OK, we're getting the
smoke again. We have a Pope!

LAUGHTER

Ooh! So we're getting the scroll.

Oh, hey! What's this?

THEY LAUGH

Ooh, this is looking promising!

I like the look of this.
OK, so let's take this.

OK, I've got the magic scroll.
LAUGHTER

- OK, so let's put this
down here...
- OK.

- ..and let's check this out.
- Let's see what we've got here.

Are we ready? This is the
number of civilisations

in the Milky Way galaxy.

Yeah, and this is just our galaxy,
the Milky Way galaxy.

So, OK, we've got five, sort of....

- OK, 50... Oh, OK, 50.
- Oh, wow!

- One, two, three, four, five, six...
- Wow.

OK, so that is 50 billion.

- OK!
- You've got a galaxy
full of life!

That's a bit more optimistic.

That is very, very much
more optimistic.

Well, first of all, a round of
applause for our volunteers.

Please, take your seat,
and thank you very much.

And thank you, a round of applause
for our wonderful contributors,

to the both of you.
Thank you, guys.

I'll let you keep it. Thank you.
APPLAUSE

And so we came up with
some interesting answers there.

It was never actually going
to give us a definitive answer,

because we just don't know,

we don't have the right
information accessible yet.

We think that there must be
life out there -

but the problem is
it might be far, far away.

So, if you could find the aliens,
the question is,

what sort of thing would
we like to say to them?

Now, we've been polling people
who have come in to the studio,

and this is the result of what
they want to ask aliens.

Do you like to sing?
Do you like to dance?

I mean, cos if you like to dance,

we could have a competition.
Yeah!

If you're thinking of coming
on holiday to planet Earth,

I don't know if it seems
big or small to you,

but there is huge variety

so you're going to need
to take a while.

What do you look like?

And is there other planets
out in the universe

that human beings do not know?

Do you have any hobbies
that we don't know about here?

Is there any materials that are
undiscovered to Earth?

Where do you live
and what's it like?

And are you carbon-based?

Do they get hungry?
Do they ever eat for pleasure?

Is water really necessary for life?

I think that's one of
the big questions that we're

grappling with here on Earth.

Hi. What's your planet like?

And what's your favourite
things on your planet?

What sort of wildlife do you have?

And do you speak English,
or do you speak Spanish?

Or do you speak any other language?

Um, I want to know, ooh,
what your plants are

and if you can breathe.

Yeah, we're a beautiful planet,
we're diverse.

It's humans and animals, plants,
and that's great.

But so much has changed,
and I think actually, we would learn

so much from meeting another
off-world civilisation.

Do you guys have a fascination for
outer space as much as we do?

Aliens! Please come to my home!

APPLAUSE

So, yes, these are the messages
we'd like to get out to aliens.

Now, this has actually
been done before,

because there were two spacecraft
called Voyagers,

and they travelled through our
solar system and went out beyond.

And this is the golden discs
that were actually put on board

the Voyager spacecraft.

So, Voyagers were launched in 1977,

and they have travelled through
space for over 50 years now,

and they've gone out into
interstellar space.

And yet, on board, they had these
records - and these records,

they're actually... So they
were very much of their time,

this is 1970s, so these are records,

and we sent them out into space

but we also included instructions
of how to play the records.

And on this, they included
all sorts of things,

but they included a map of where
we sit in our solar system.

They included sort of
the laughter of children,

sort of children of the
Earth saying hello,

and sort of the music of Beethoven,
and many other things.

Now, because this is
the 200th Christmas Lecture,

I thought it would be wonderful
to do the same thing.

So what we've done
is collected all those messages

and put them on this disc.

And now, I haven't got the
capability, and we haven't got

the budget to send this into space,

so what I'd like to do is,

please welcome the Director of
the Royal Institution,

Katherine Matheson.

APPLAUSE

Now, Katherine, what I'd like
to do is give you this disc

that we've created,
our own Golden Disc,

and hopefully it can join
the archive here at

the Royal Institution.

- So, thank you very much.
- Thank you so much, Maggie,

and thank you to everyone who has
contributed to this amazing record.

It's a real privilege to have it
here at the Royal Institution.

It's a really special year.

As you know, it's 200 years since
the Christmas Lectures

were started by Michael Faraday
to share the joy and wonder

of science with young people,

and that goal feels just
as relevant and important then,

in 1825, as it does now.

So, thank you very much
to all of you,

and especially for being
our 200th Christmas Lecturer.

- Thank you, Maggie.
- Thank you very much.

And a round of applause
for Katherine, please!

So that brings us to the end
of this lecture,

and I must admit,
I'm tearing up a bit because,

as I said, I used to sort of
always want to come and see

the Christmas Lectures.

I never got the opportunity,
but it is...

I feel so honoured to be here
with you tonight.

Now, as a child,
I was at the back of the class,

I wasn't considered very bright.

I went to 13 schools,
and I have dyslexia and ADHD,

so I never thought I'd be
standing here in front of you.

But I think this is the key.

Have a big, powerful dream

and see where it takes you.

All my life, I have been reaching
for the stars - literally.

I have wanted to get out there.

And in this lecture,
we have done just that.

We have gone to the very edge
of the Solar System.

What I hope for in the future,
and especially for you young people,

is that as we make that journey,
we do it in the right way,

we do it for the benefit
of all humanity,

and we learn from our past mistakes
and make sure we actually go out

into space in an essence of unity.

So thank you very much
for having me here,

and thank you all so very much
for support from CGI.

And for that, that's it from me,

wishing you all a
very, very merry 2026.

Thank you very much, and goodnight!

CHEERING AND APPLAUSE

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