Original subtitles

This is where the adventure starts for me.

1975, and my parents take me downstairs to watch the Apollo -Soyuz test project,

the final mission of Project Apollo, and its famous first handshake between

Russian and American astronauts.

40 years later, and we see the fruits of that collaboration.

up there on the International Space Station, Tim Peake's mission.

That platform is a platform for peaceful collaboration in science and

exploration, and it is the jumping -off point for new adventures.

This lecture is all about the next frontier, and that frontier is

your frontier.

Thank you and welcome to the 2015 Christmas lectures. I'm Dr. Kevin Fong.

medical doctor and I used to work with NASA helping them protect astronauts as

they went about the business of exploring space.

This is the final lecture in our series and in this lecture we have our sights

firmly fixed on the future and what it's going to take with the edge of all that

science, technology and engineering has to offer us to protect astronauts.

astronauts as they go about trying to go further and deeper into space.

But first, let's go to Tim Peake, the space station, to the ISS to look at

the unexpectedly dramatic start to Tim's first few days aboard the station.

Up on the screen just there, you can see Tim, who's reading a checklist. On the

other side of that door are his crewmates, Tim Copra and Scott Kelly,

the airlock, in their suits, getting ready to go out the door on a spacewalk,

which is pretty much the most dangerous thing that astronauts ever have to do.

Now,

we'll be seeing more of how that spacewalk turned out later on in this

But first, let's have a look at how much of space we've already visited.

Now, let's make a constellation of everywhere we've been to explore.

Now, these are our lights of exploration. And this is the first light

Sputnik.

You're going to be Sputnik for me. Who's going to be Sputnik? Well done. All

right. So Sputnik in 57.

And then in 61, the first human, Yuri Gagarin, goes into low Earth orbit.

And by the end of that decade, famously, we're on the moon.

Six crews, 12 people to the surface of the moon. And in that same decade, we go

to our neighbors.

Mariner 4 in 1964 takes the first photograph of the red planet of Mars.

And then we go to our nearest neighbor, to Venus.

And then we master the art of the slingshot and we're going to Jupiter and

off to Saturn and then Moon and suddenly nothing in the solar system is beyond

our reach. We're into Mercury, we're out to Pluto and now we stand with Voyager,

the most distant man -made object from the Earth at 50 billion miles from

And this is the constellation of exploration in space today.

But wait.

Where have we been with humans? Everyone who doesn't have a human mission, turn

off your lights now.

And what are we left with?

We're left with low Earth orbit and the moon.

And there's a reason for that.

Rocket science is hard enough before you start trying to include people as part

of the payload.

But with everything that we've learned in the history of human space

exploration, we're ready to go again.

And particularly with the lessons we've learned from the mission that Tim Peake

is now involved in aboard the ISS, we are going back to the moon. We're going

go off to Mars and perhaps even more exotic destinations.

And this time, we're going with people.

But where might we go?

Well, we could start with the moon. There is unfinished business there.

And to explain what that business might be and why humans should go there, I'd

like to welcome our very first guest, planetary scientist Dr. Katie Joy.

Katie, I'm more of a Mars man myself, so convince me that we need to send humans

back to the moon, because we've been there. We've been there six times, 12

people. We have, but we might have been there, but we've certainly not done

that. So we've sampled the near side of the moon from just six places. All that

moon rock came back, it's located over at NASA, but scientists around the world

are still studying it to try and understand the moon's path, and also to

understand the moon's place in the solar system. So we need to go back and we

need to get more to really understand it. There's a lot more still to do. But

really, because I mean...

There needs to be something really, really valuable up there to make it

going. What is it that we would learn from the moon that would be so vital to

here on Earth? So we can actually study the moon to understand our own origin,

so the origin of Earth itself. But what's really exciting is the idea that

may actually be early Earth material on the moon.

Samples, geological rocks from when life first started on Earth. Now, these are

not well -preserved on Earth because we have active plate tectonics, we have

oceans, we have atmosphere that destroys these ancient rocks. But who knows? Big

asteroids and comets were striking the Earth, and they may be able to chip

little bits off. That can travel through space, and maybe they're just landing

on the moon, ready for us to go and find. Do you know what I think we're

to need? I think we're going to need a volunteer.

Who would like to volunteer to help us explain this?

All right, let's go up here and duck under there and we'll have you.

Yeah, come on.

What's your name?

Joseph. Joseph. Joseph, you're going to help me. You're going to need these.

All right, Katie, I've no idea what we're going to do here, but you tell me.

Okay, well, we're going to pretend this box is the early Earth, and this is

examples of ancient rocks sitting on the early Earth.

We're going to pretend that these guys, here we go, we have some pretend

asteroids. They look like iron meteorites to me. And we're going to

the Earth's surface. So here we go, Jason. All right.

Goggles on.

Sort of dangerous. Come on then. We're going to try throwing some into the box

and the objective is to kick some soil out and have it try and hit the moon. So

surface of the Earth, moon, you've got to get some rocks onto the moon to

convince me we need to go there. Go for it. Okay.

Oh, Alex, you're going to need some goggles for this one because this is

overwhelmingly, overwhelmingly dangerous throwing stuff into that. Okay, here we

go. Joseph, give it your best shot.

Okay, we're not... We're not doing a grand job, so we're sort of throwing at

speeds of, you know, a couple of metres a second.

So what we need is to ramp it up a little bit. I told him he needed

look a bit stupid now, don't I?

Why isn't this working? Why can't you get the rocks off the Earth onto the

here? So when asteroids and comets hit the Earth, they're travelling at

hypervelocity impact. So we need to get material up about 11 kilometres a second

being spooled off. I think I have a hypervelocity impact simulator specially

built. This is our hypervelocity impact simulator.

It's very high -tech.

And, Joseph, you're going to help me fire it off. OK, Alex, you ready for

OK.

Our asteroid or comet is travelling closer and closer to the Earth. It's

getting ready to go. We're getting to the right sort of speed.

Let's count in. So three, two, one, go!

Hey!

Sorry about that, Alex. You need a

new set of clothes as well as that.

so there's rock all over the moon all of a sudden and that's I guess what we're

looking for Joseph thank you very much for helping us ladies and gentlemen

Joseph thank you

Katie, you have brought some of the moon with you tonight. Show me that. Show me

that. So I have some small chips of Apollo samples that were brought back by

astronauts. And we actually have a beautiful thin section of lunar rock

the microscope that you can see here. So this amazing sample, it looks like a

stained glass window when we shine light through it. And this is actually a lava

flow. Here we go. We've got it on the screen.

So you guys can see some spectacular...

colours. All these different colours represent different minerals and these

formed in a lava flow that erupted from a volcano about 3 .2 billion years ago.

That's just amazing. This is a piece of rock brought back by the Apollo

astronauts nearly 50 years ago now.

Yeah. And you studied it as part of your PhD, didn't you? Yeah, so we study

rocks like this to understand the Moon's volcanic past. This one came from the

Apollo 12 mission, so the second mission that went to the Moon. But rocks like

these may be really good traps for preserving some of these amazing

meteorites and maybe Earth samples that have been delivered to the lunar

surface. But they're incredibly beautiful to look at as well.

Absolutely beautiful.

It's amazing that so long after the end of Project Apollo, they're still

teaching us valuable lessons.

Sounds like a job for a planetary geologist like you on the Moon.

Would you go to the Moon? So we did get one geologist on the Moon on the last

mission, and I would love to be a future geologist.

I might try applying again next time. We'll see what happens.

Yeah, you applied to be an astronaut, didn't you? I did. We'll keep trying.

Maybe somebody else in this room can have that opportunity to do it.

Katie, fantastically, you have convinced me we've got to send people back to the

Moon. Thank you very much. Thank you, Joy.

Thank you It is incredible really that we were able to go to the moon not just

because we left behind on earth when we went to the moon everything we take for

granted in terms of life support here on earth, but because we also left behind

our Protection from radiation the protection we get from the earth's

field now Right now, Tim Peake is on the space station very carefully monitoring

his own levels of radiation using a clever detector called the TimePix

And to explain a little bit more to you about this, I am going to need a

volunteer. All right, let's go on a bit of a space mission.

Let's have you.

What's your name?

Celeste. Celeste, put some gloves on.

We've got some bizarre stuff to show you here.

Celeste, have you ever seen one of these things before? Do you know what this

is? No. No, this is a Geiger tube.

Anyone else ever seen one of these before?

Yeah, yeah, yeah. Okay, and it measures radiation.

Okay, so we're going to turn it on.

Ooh, there you go. Now, Celeste, point that...

At the audience, see how radioactive they are. This is a Geiger Schube. It

us how radioactive things are. The more radioactive they are, the more clicks

you get off of this.

It measures the ionization.

Radiation comes in the front. No? No radioactive people?

How about over there?

No? Okay, let's point that up to the sky.

No real radiation.

Hmm.

That's because we're under a blanket of atmosphere and the Earth's magnetic

field. So to show you some radiation, we've had to find something radioactive.

And here at the Royal Institution, Charlotte, our curator, has some very

sources of radiation.

Go on, point it at this book.

Charlotte, what is this book?

This is a notebook from William Cripps from 1903.

Ah, and William Cripps, I remember, he's the bloke who made the very first

medical X -ray tubes.

Yes, indeed. That's very radioactive.

I might take that.

All right, now this book, this is the page where he was talking about messing

around with some radium salt.

Yes, radium bromide. That's radioactive stuff.

I think he was messing around when he was writing his page. Now, which is the

worst bit on this book? Dan Chris.

OK.

Oh!

That's not good at all.

OK, so...

It's very, very, very radioactive. Where do you keep this book, Charlotte?

In the RI archive.

Yeah, but what?

In a metal box. In a metal box, okay.

Now, it's okay as long as we don't eat or lick the book, okay?

So do not eat or lick the book.

Now... All that does is tell us how much radiation is there. So to do something

rather more interesting, we'd like to know the sorts of radiation and how many

particles. We're going to use the detector that is on Tim Peake's mission.

is the time peak detector. You're going to help me start it. So you're going to

go round the front there, and let's see how Mr Crook's book does.

OK, I'm going to take off the cover now over that page.

So every spot is a particle. The bigger the spot, the higher the energy. Here we

go.

And let's have a look at what.

We see the book has suddenly... Oh, here we go.

Here we go.

And so all of those dots that you can see there are all particles of radiation

or photons of energy coming through that detector.

And I don't think you can see it quite as well as we can see it here, but

Celeste, that's a lot of particles, isn't it?

Charlotte, I don't want to stand near this book anymore, so I think you should

take it away. And Celeste, I think your mum would be really happy if I sent you

back to your seat as well. Thank you very much, Celeste.

So lesson one is don't eat radioactive things, but we have some data from the

space station from the detectors that Tim Peake is using and this is it. And

help us understand what we're looking at, I'd like to welcome my guest, solar

physicist, Professor Lucy Green.

Lucy, what is that? It looks very worrying. That detector tells us sort of

just how much radiation, but the type.

So what type of radiation is doing that?

So this detector is able to pick up electrons, protons, and also heavy

nuclei that come streaking in from all over our galaxy, travelling at almost

speed of light.

Sounds slightly nasty.

We don't have to worry about those so much here on Earth.

You've got something here to explain that to me. That's right. So this is a

setup called a planetarella, and it's a really nice way to demonstrate both the

fact that the Earth has a magnetic field which guides electrically charged

particles and also the effect of electrically charged particles on the

atmosphere. And what's happening in here is that...

electrons charged particles are being accelerated through an invisible

field and you can see that on around that small sphere glowing lights and

equivalent to the northern lights and the southern lights the aurora it's very

very beautiful even here but there is a more beautiful way of seeing this and

that's to be in space and i think we've got some video of the northern lights

i've seen some space look at that That green glow in the top, that's the

Northern Lights, isn't it? And this is from Space Station looking down. It's

such a fantastic view. The astronauts have the best view of the Northern

I'm so envious of what they get to see. You see the thin atmosphere, you see the

green glowing oxygen, but for us it's incredibly important because it...

acts as a blanket to block out the effects of those galactic charged

that we saw earlier on. So we can protect ourselves from the most harmful

radiation by sitting inside our blanket of magnetic field.

So are we all right to keep going and exploring?

Well, there are difficulties that we have to overcome, really severe

difficulties. So we've talked about particles coming from the galaxy, and

talked about the fact that the Earth has a magnetic field and an atmosphere.

There is some protection from these galactic particles that we get from the

as well, and we see that the number varies across the solar cycle. The sun's

magnetic field extends out and surrounds the Earth, and it deflects the galactic

cosmic rays from us.

But the sun is both our friend and our foe. And the sun itself is an amazing

particle accelerator. And it's able to produce events where particles like

electrons and protons get...

accelerated almost to the speeds of light as well, and they shower down on

Earth. So whereas the particles coming from the galaxy have very, very high

energies, they form a sort of background radiation.

The sun is capable of these very strong, high -flux bursts, and they can be

very, very dangerous for astronauts.

And I'll give you a bit of information about the normal flow of particles in

solar wind. So the sun all the time has a flow that takes a few days, maybe four

days, to get from the sun through 150 million...

Kilometers of space to us when an energetic particle event happens they

within half an hour and The storm can go on for days and then there are so many

of them

pouring down onto the astronauts. Once you're above the Earth's atmosphere and

at the edges of the Earth's magnetic field, you have very little protection.

fact, the particles are so energetic, they don't even see our magnetic field.

They just come rushing in.

And so if you're an astronaut, outside the protection of the magnetic field and

one of these solar flare, solar particle events happen...

What happened to you?

So you would be irradiated, and you could have a mild effect. You could get

radiation sickness, disorientation, but it could be fatal.

And Tim Peake's crew has just gone out on a spacewalk.

sort of event have been a risk for them if they were outside their vehicle on

that spacewalk?

It would have been. So they would not have been allowed to go out on a

had there been a solar particle event happening. They are so dangerous. They

would have to have been inside the space station and also gone to an area where

they get more shielding because to stop them, what you want is material that the

particles can run into, collide with, and then not reach your body.

But this sounds like a disaster because we want to go exploring the rest of the

solar system and it sounds to me like we should just stay at home and... power

underneath the Earth's magnetic field and our atmosphere if we can.

It's a huge challenge, and I think it's the main challenge to overcome if we do

want to successfully move out towards Mars. It's got to keep humans safe. It

doesn't sound like we can. I can't build a spaceship out of lead. What would you

do about shielding, Lucy?

Some people are thinking about using the water that you would need. Water's a

good shield.

That would be a good shield. In fact, it turns out that having a material that

has light particles in it, like hydrogen, is quite a good approach.

So water, OK, it weighs quite a lot. but it would make a good shield if you had

it running through the walls of your spacecraft.

Lucy, thank you so much. Thank you. Now,

they're not just measuring the radiation environment inside the space station,

they're having a look at what effects that has on life outside the space

station, and particularly with this particular facility here.

Now this is the exposed facility and it's a British -led experiment up on the

space station right now with Tim Peake. This has been taken up and then bolted

onto the outside of the space station and it's pretty cool.

Inside you have layers, and it's outside the space station, and they're exposing

the contents of this to radiation. Now inside, there are fungi, there are

bacteria, there's even some seeds, and they've layered it so that one layer is

the same as Mars in terms of radiation environment, one layer is the moon, and

one is just a vacuum of unprotected space.

And you think that everything should die up there.

But some of this stuff does reasonably well, and there is one creature in

particular that is just incredible in radiation.

We've got some right here, if they haven't run away. Now let's have a look.

These are tardigrades.

This is a super tough creature.

You think you'd do well against this creature, but you wouldn't, because you

boil it, and it says, meh.

And you can freeze it down to nearly absolute zero, apparently, and it

care. You can subject it to huge pressure, and it doesn't care. You can

to space without a spacesuit. To be fair, it was very hard to make a

for these things.

And most amazingly of all, you can subject it to huge doses of ionizing

radiation, and it kind of likes it.

That is a tardigrade. They're also called water bears, and some people

they're a bit cute.

I think they're just kind of weird, really, but they're super tough.

Now, the tardigrade can survive doses of radiation that none of us can, and

radiation is super bad for you. It can damage your cells at the molecular level

and cause all sorts of problems with your DNA and your DNA's ability to

replicate and produce healthy new cells.

So how...

Does the tardigrade manage to survive when we would do really, really badly?

And for that, I am going to need not one, not two, not three, but four

volunteers.

Let's go here.

And let's have you.

Okay, come on.

Okay, and okay, off the front row. Okay, how about you? Good. And one more from

over here. How about you? Okay, come on, let's go.

okay over this side okay so you are going to be team tardigrade this is a

tardigrade dna double helix and you are going to be team human which you would

think would be good but just wait this is a human dna double helix you are the

repair mechanisms for this DNA.

And in a minute, we're going to expose them to some radiation, and you are

to try and repair them.

But we should get out of the way of the radiation, because we're about to

irradiate this whole field. Come on, follow me, quick, let's get out of the

Come on, come on, come on, come on.

Let's go.

Now, the rest of you, while we're clear of the areas, should prepare your

radioactive particles.

And so I'm going to... Everyone ready?

Yes!

Okay.

Three.

Two one irradiates

Okay,

there was a bit of damage there and then there was a solar particle event

Okay,

so I think you might need some help with these so we'll get some people to help

you I hope you remember what they looked like before

because I want you to build exactly the same DNA helix. So, repairer, team

Tardigrade, are you ready?

Yes. Oh, wow.

Team Human, are you ready?

Yes.

They brought it. They brought their game.

Okay, three, two, one, repair!

So, right now, they are trying to repair the damage that was done by your...

Frankly, not very good irradiation.

And they're trying to build the towers that existed beforehand.

Now, Team Tardigrade here, doing all right, I suppose.

And Team Human, they're nearly there. So, Team Tardigrade, basically, hurry

Are we nearly there?

Well done. All right, well done, guys. All right.

All right, come and stand here.

Fantastic, and come and stand here. All right, now let's see how you did. Now,

in a minute, we're all going to look at the screens and see before and after.

Okay, so right up on the screen, this is the human tower, before and after.

You haven't done bad, actually. Silver row, and then the green row, and then

blue row, and then... Hold on.

Blue and green, yellow and green.

Oh, dear. And then it goes completely wrong, and...

You really haven't done very well. That is not a good repair job, people. So too

quick, I think. Okay, let's have a look at Team Cardigrades before and after.

So two silvers, two greens, two blues, two blues, two greens, two yellows.

You're perfect all the way up to the top.

That's amazing.

Well done. Team Cardigrades wins.

But, but... You did have a bit of help, didn't you?

And not just from John, because Team Tardigrade, I'm sorry to tell you, Team

Human, had a little guide to how to put their tower together.

And do you know what?

That's the trick. That's how Tardigrades do it. Tardigrades have a superior

repair mechanism, so when they get hit by radiation, they can repair their DNA

better and much more effectively than humans.

So Tardigrades win, at least in a radiation field.

Ladies and gentlemen, thank you very much. Go back to your seats. Thank you.

And radiation is a huge problem if you want to carry on journeying deeper and

deeper into space, and particularly if you want to go to my favourite

destination, and that is the planet Mars.

Now, as far as we've ever been from Earth is the moon at 250 ,000 miles.

about the distance that you can get a car to drive before the engine falls out

the bottom.

But Mars sits out there...

Huge distances.

It is the fourth planet from the sun. To get there, you need to travel for

hundreds of millions of miles.

The time for a mission to Mars is at the very least about a year and a half and

maybe up to three years.

So you're talking about a thousand days in space, which is crazy.

And then you start to think, well, what am I going to pack?

Well, packing for space is hard.

And to help me show you that, I am going to need a volunteer.

Okay. Okay. All right.

Let's have you.

Thank you.

What is your name?

Asha.

Asha. Ashta. Ashta. Ashta.

Ashta, this is your suitcase. I've packed it for you, okay?

For a weekend on Mars, all right?

And this is pretty good.

So what do you think you need for a weekend away?

Some clothes?

Yeah, yeah. Space suit would be good. We'll start with a space suit. Well,

let's... So come round here. Just stand here.

Perfect. So space suits. Well, space suits. We can... Space clothes. Space

clothes is close enough. So let's have some of that. All right. So we've got

some space clothes.

Okay. You're going to have two pairs of pants.

It's a weekend. Let's get two pairs of pants. Okay. I think they're in there.

All right. So you've got... You've got clothes.

What else do you need? You probably need to take some food, don't you?

Yeah. So, Ashta, here's some food for you.

Let's find the food in here.

Oh, yeah, here's your food.

So, we've got some space food for you. This is sausage casserole. You're a fan

of sausage casserole?

Bit of flour and... Oh, what's that one there?

A bit of toffee pudding. Toffee pudding. You up for that?

okay all right and uh what else have we got so you've got to take your water

with you now if you were an adult astronaut you need to take uh about

liters a day so we'll get liters of water out so six liters for the whole

and it's not just your water is it you've got to take your oxygen so here's

life support for you all right um let's just get that there and it's not just

your oxygen you need a towel don't you to dry yourself off this is a very nice

towel actually look it's got a good message for people who are in space all

right um and uh what else would you want some reading material ashta uh cuddly

toys um and and a wash kit And that is for two days in space.

Okay, so multiply that by 500 for 1 ,000 days in space. Multiply that by crew of

six, and we're in trouble, aren't we? We're never building a spaceship big

enough. You're dropping it all, and I'll pack that very carefully for you. We're

not ever getting into space flight, are we? No.

Asta, we're going to have to think again.

Thank you very much, Asta. Thank you.

It's not going to work, is it? We can't pack like that for Mars, because the

spaceship would be so big, we'd never get it off the ground, let alone get it

hundreds of million miles into space.

So how are you going to do it? And the answer is, you're going to have to get

better at reusing everything.

And I really, really, really mean everything.

Now, for this next one, I am going to need a volunteer.

So, now, this...

Here's a glass of my finest urine.

So, I need a volunteer to drink this urine.

Okay, okay, let's listen.

When someone says, I need a volunteer to drink urine, you do not volunteer for

that, okay?

That's the most important lesson I'm going to give you today.

Are your hands still up?

Really, it is not socially acceptable ever, ever to drink urine, okay? There's

reason you have kidneys, and that's because the stuff in your urine, the

that your kidneys takes out, the potassium, the sodium, the urea, the

creatinine, the phosphate, that 5 % of the urine is really, really bad stuff,

which is why you put it on the outside of you, okay?

So when someone says, do you want to drink my urine? You say, no!

There is only one acceptable way to drink urine.

And that is if you have some special treatments.

And so this is a special bag that recycles urine.

And what it does, it's a bag within a bag.

And I think I'm probably going to need another glass here. But there's a bag

within a bag.

And the bag inside is actually a semi -permeable membrane.

And you put...

pee into this red port here, the urine goes into the bag, and then the bag on

the inside will allow water to go through, but not all the nasty stuff.

Now, to encourage the water across, this green port, you put a syrup in, and the

syrup has a very high osmotic pressure, lots of molecules that draw the water

across, and you get clean water with all the nasty stuff left outside.

This, very helpfully, if you can see that there, has a port that says, dirty

water in.

Sport syrup in, clean drink out. So do not drink out of the red port.

This is one I made earlier because osmosis takes a while.

And we're going to pour it in here now.

Now, here's the thing. Because you've got some syrup in there, it kind of

a little bit like pee, even after it's been reprocessed.

And to be honest, do you want to have a smell of that?

It smells like... Smells quite a lot like urine. Yeah, it smells quite a lot

like pee. Do you want to smell?

So it looks a bit like pee and it still smells a bit like pee.

But this is perfectly safe to drink now because osmosis has treated it.

And... To be honest,

it really does still taste like pee.

All right.

Now, Tim has a much better way of recycling his pee. He does recycle it up

there. Tim Peake and his crew have a really quite cool mechanism which not

recycles their urine, but also their sweat and the vapour they breathe out of

their mouths.

they're recycling up to 98 % of their body water.

That's really horrible, that stuff. It's just so horrible.

That is how you recycle urine.

But what if you had a way of recycling water that was also a way of recycling

your atmosphere, that was also a source of food? And I have one of those right

here on the shelf. It's called a plant.

That's what you'd like to do. You'd like to take a bunch of plants with you into

space. But that turns out to be really, really hard because you're in a

spaceship and there's no natural light and there's no soil because there's an

infection risk from the soil. So how do you just grow plants in space?

I don't know, but I know a man who says he can.

And let's welcome Alistair from the Royal Horticultural Society.

Alistair, I'm going to put this down.

Now, what's this?

This is a clause system that will feed us. It produces the food for you

to eat.

So this is grow your own space food, is that right?

Yeah, yeah. And you can do something with that to make something that I would

want to eat?

Yeah, yeah. It'd be a bit smaller, but yeah. I'm not convinced, but you tell me

that I will be, so...

To show me, I'm going to need a volunteer.

All right.

Let's have you. Okay, good.

All right.

What's your name? Finley.

Finley, you're going to go over here to Christian, who's going to help you over

there. Apparently, you're going to put something together that we can grow over

here in space, apparently.

All right.

Convince me of this, because I'm just not buying it. So what have we got? This

is a system that you can grow in space.

How is that possible?

We've got no sunlight in space.

So the light here, you've got red and blue lights. Now, plants photosynthesize

at the red and blue lights, so it optimizes the amount of chlorophyll A

relation to efficiency.

You also have some green lights in there.

You've got a water system here, which is a closed water system because there's

near zero gravity.

Water would be floating out of this at the moment, which is why they're

completely closed in those systems.

And so this is a system that could be grown in space, and I think the guys

tried to do that.

There's a video of that up here on the screen. So this is some weird space

plants. What colour are those plants?

Yeah, so this is the veggie plant. They're the purple plant.

Why are they purple?

Well, it's in relation to the anthocyanins that they have in it. So

chemistry within those.

Anthocyanins, those are the things that make leaves turn a different colour.

That's right, yeah.

And you can see that it's a collapsible system. So this is called a veggie

system and it'll leap, leap, sort of come up.

And what plants have we got here? What have we got? I mean, I've heard of five

day, but this is ridiculous.

What's this?

Okay, so we've got rice here. Yeah.

We've got wheat here. Yeah.

We've got basil.

Yeah.

We've got soya here.

And we've got tomato here. So there's a number of crops here that we would

probably want to take up. Really? I can see how you could grow this all in

space, but what food are you going to make with that?

Ooh.

Finlay.

What's going on?

We're trying to grow space food here, and you're just mucking around in the

kitchen. What's going on?

Hopefully pizza.

Hopefully you can make a pizza with all that. Oh, yeah, you can make cheese.

Space pizza.

Christian, let's see some space pizza in your special space -age oven.

Ladies and gentlemen, space pizza.

I think you need a bit more basil on there. Finlay, come and grab some of

There you go. Go and sprinkle that on off of our hydroponic system.

All right.

Who's the hungriest cameraman?

It always looks like Joe. Joe, let's be Joe.

Brilliant. All right.

Let's make sure that Joe can... You just carry on with that, Joe, while we carry

on with the programme.

All right. Okay.

Alistair, Finlay, thank you so much. Great to see you. Thank you.

Okay, so even if we master the art of bringing our life support with us in

sort of form that we can regenerate, we've still got other problems. And

part of the mission of Tim Peake's crew aboard the International Space Station.

So let's go back to that emergency spacewalk that Tim's crew had to do at

start of his mission.

Astronaut Dan Tarney is going to talk us through what is possibly the most

dangerous thing that any astronaut ever has to do.

Dan, why are they having to do this spacewalk? This wasn't expected. This

in the plans for Tim. He wasn't expecting to get up on the space station

almost immediately have to help supervise a spacewalk.

Absolutely. They were doing a routine move of what's called the mobile

transporter. And the mobile transporter is like the trolley that goes back and

forth. Yeah, let's talk about that.

And so they were doing a routine maneuver from one worksite to another,

unexpectedly it got stuck. It had to release from one worksite.

And it got stuck between before it could get to the other work site. And they

don't know why.

And that's a big deal because they depend very heavily on that arm. It's a

big deal because two of the supply ships that bring cargo to the space station,

the food and the experiments and sometimes oxygen and critical things,

grappled by that arm. And right now that arm is completely useless. It's not

hooked up to the space station. And so they need to get that arm, that mobile

transporter, locked into place.

The arm can be operated.

They're going out of the lock there.

Yeah, here they go, yeah.

If they are unsuccessful at performing this EVA, it will put a halt to

everything on the space station. They have got to fix this mobile transporter.

They cannot continue operating the space station with the mobile transporter in

this position.

This is a helmet camera. You can see their perspective of what they're doing.

Okay, I'm going to start heading that direction.

All right, sounds good.

So they're navigating their way to their destination, and that's what they're

doing now, right? Hand over hand, working their way around this structure,

that airlock, and out towards the theta cart, this transporter we've been

hearing about.

The space station is so large, there are labels out here.

with arrows that say airlock so that you know how to get home we'll see those

because it because the last thing you want is to be so disoriented like i

i'm not sure where i'm going and so we have basically how to get home arrows

there Is it easy to get lost on the outside?

It's very surprisingly easy to lose your orientation and not be sure, am I on

top? Am I on bottom?

Am I behind? Especially if it's dark and all you see are a couple of handrails.

Right, and that's a good point to make because right now they're in sunlight.

they time the walk to start with an ISS sunrise and then they've got 45 minutes

before the sun goes down again and then this view will go dark and only be

illuminated by their helmet light.

There are a few external lights on the space station, yes.

Let's have a listen to the downlink, if you can hear it. Pedal on the starboard

seat of cart will initiate the release of the brake handle, which is believed

on the starboard seat of cart to be the suspect that is preventing the movement

of the mobile transporter.

It's started moving forward now.

Okay, we copy that.

So they are at their destination now. They're there. Yep, they're working it.

What they want to do is make sure that the brake is the problem and there's no

other problem.

I've got the fair lead on the major stanchion of the port spread on the

Okay, copy that. Then you can go ahead and translate up to phase one, and

looking for handrail 3523, which is in bay 02 for your green hook.

So that's a very specific instruction, isn't it? So just not the handrail, a

numbered handrail, and telling him where he's going to find it. I mean, how

useful is that information to you when you're walking?

Oh, it's critical.

What they're instructing him to do is go to that handrail and take his safety

tether and attach it to that handrail because in the whole choreography, they

don't want to cross their tethers or get it caught up in anything else.

So right now, Tim Peake is still in vehicle. I guess he's probably

their progress. Oh, yeah, he's certainly monitoring what's going on, making sure

that he understands where everybody is. But he has to be acutely aware of what's

happening on the outside so that if anything happens, he's ready to jump

action and receive them in the airlock again.

And it sounds like they might just be about to get this cart moving.

They've done everything they need to do on the seat of the cart, and it sounds

like they're giving the go and getting out of the way so that the cart can

They're going to get out of the way so that mission control can move. cart

automatically from the ground so there's an instruction going to be issued from

mission control and get that cart moving and we're going to give that next

couple of minutes okay i'm ready for motion whenever tim and you guys are and

i'm ready for motion too scott okay we're putting in the last command

i see motion and we do see motion on the mobile transporter motion

down here as well that's good that's good as well It's an inching tool.

Yeah, very slowly.

Okay, guys, good news. It appears to have reached the worksite center.

So we are a go to continue. It's a big success.

They couldn't be happier with how things went on this spacewalk show.

I'm going to tell you to stop there for a second. Okay.

Right when you get to that trunnion pin.

Okay, we'll be right back.

That's taking a picture of Tim Cobra. That's what he's doing. He saw a good

picture, so he's setting up a picture. All right. So enough time for selfies.

I think they're doing pretty well.

That is remarkable.

So the crews have got out of the airlock. They've got onto the bit of the

station that was broken.

They have got that break off. They've moved into place.

Tiny fingers crossed to make sure that that couples into the power so they can

move it again.

But I think that they have.

Literally, save, dismiss, and I think that's a round of applause. I believe it

has.

So exciting stuff, but only 15 people have ever flown for more than 200

consecutive days in space. Two of them are in orbit right now. One of them is

Scott Kelly, the guy on the right in this picture.

And he's trying to work out the effects of space on the human body to prepare us

for that next great leap into space.

And he's pretty good in space. You can see he's very comfortable.

He's all there.

But he is still trying to find out.

how survive for longer and longer. That's the goal of this one -year

Now, right there, you can see him on the space gym. He has to spend a couple of

hours a day on that just to preserve his muscles and his bone and trying to

preserve his heart, because otherwise he comes back like a big, fat couch

potato.

And the problems that you have because of weightlessness, you can avoid if you

do with gravity what we do with our lights, our heat.

Our sources of power, our drink, and our food. And that is, take gravity with

you. Now, that's not as sci -fi as it sounds.

That's easier said than done. All you need to do is to make use of a bit of

circular motion, a bit of centripetal acceleration, and a bit of centrifugal

force. We've got four astronauts on this mission.

Are you nervous?

No? you really really should be um this didn't go well in rehearsals here we go

okay and there we go on our space mission oh my gosh

okay oh

so

that was another partial success i think um but but you get the point if you can

spin something fast enough and hard enough you can create um It's not

gravity, really, actually. This is acceleration, and acceleration and

Einstein told us, are equivalent.

So this is gravity, really, in a sense, when we spin the vehicle. But here's the

problem.

To get a lot of gravity, if your circle is small, you need to spin very, very

fast.

And the only way of producing adequate gravity and not spinning fast... and not

making yourself horribly, horribly dizzy, is to spin something big.

Now, bizarrely, NASA have done those experiments.

When you look up on the screen, we can see some experiments. When we get this

mess cleaned up, we can see some... I think this is from the 1960s. This is

trying to work out how big a radius and how fast you can spin people to get them

to tolerate...

rotational vehicle so that you can create artificial gravity. Now this

been suspended by the crane above him on his side and he's walking around this

rotating structure and what they found when they did lots of these experiments

is that everyone gets busy at a point but some people, there are some rates of

rotation that everyone can manage to cope with and

That rate of rotation is four revolutions a minute. No matter how bad

a fairground ride, after a certain amount of time, you can all manage four

revolutions a minute.

Okay, so if that's your limiting factor, if you have to spin the vehicle at four

revolutions a minute, and you want to make one g of load in that vehicle, then

how big does your vehicle need to be? And I'm going to save you the math.

here, because the answer is a vehicle with a rotating radius of about 62 .5

meters. Now, how big is that? It is actually exactly the same size, almost

exactly the same size, as the London Eye.

Now, who's ever ridden in the London Eye?

Okay, it does not go around four times a minute. If you're on it, and it goes

around four times a minute, try and get off, because it's going wrong.

But we can make it turn at four revolutions per minute.

And that's what it looks like going around at four revolutions per minute.

All the people on it that day wanted their money back.

But if this was your space vehicle going through space, turning at that sort of

rate, then the people in the pods wouldn't be standing on the floors,

on the edges, being able to stand up, because there'd be 1g of load.

1g is the force of gravity we have here on Earth. That's great.

But that's... London Eye is as big a cross as the Space Station is long, and

takes a lot of effort to build that. It took 15 years to build Space Station.

And sending vehicles like that to Mars is a huge, huge engineering challenge.

So what other option do you have?

Well, when I worked with NASA in 2007, I was part of an experiment to answer

that question.

And we thought, what if you could get a centrifuge?

that you could fit inside an ordinary vehicle. So inside a module that looks

rather like that, so as big as that, that you could send up into space on an

ordinary rocket, and you could spin something quite fast to generate

gravity. And you can do that. You can get a centrifuge that would almost fit

the floor here, and I think we've got some footage of that.

This is the short radius centrifuge in Houston. That is my former mentor at

NASA, now the director of life sciences, director at Johnson Space Center. He's

got his eyes closed because I don't think he really likes being on it very

Now you say, that's going to be rubbish, flying to Mars, spinning on that all

day. But here's the kicker. You don't have to spin on it all day. If you spin

really fast, if you spin fast enough to give you more than one G of load, then

you can give gravity like you would give the dose of a drug. And you can take

that gravity dose twice a day for one hour in the morning, one hour in the

afternoon, and that is enough to provide quite a lot of protection.

The absence of gravity, which has been your enemy all along...

isn't a problem. Actually, when gravity returns, it is your enemy.

And to get safely onto the surface of Mars, you need to be able to stop.

And there's one thing that rocket scientists will tell you, and that is

hardest two things in all of rocket science are starting and stopping again.

And so I thought we should bring on an expert in stopping when you get to Mars.

So it's my great, great pleasure to welcome our very special guest, an

from the Jet Propulsion Laboratory in Pasadena, and one of the lead engineers

the Mars Curiosity rover, Dr.

Anita Sengupta.

Now, Anita, come and give us a hand here. You've got you two. Yeah, yeah.

and give us a hand. Stretch this out. What have you got here?

This is a diskette -band parachute, and it's specially used on Mars. And the

reason for that is on Mars, when you enter the atmosphere, you're coming in

very, very fast speeds. And specifically, when you deploy the

coming in at supersonic speeds.

I'm experiencing all sorts of dynamic instabilities here with this parachute.

Have we got a working version of this? We do, actually. So we have one which is

a subscale version. It represents about 3 % of the scale that we used on Mars,

which we can show you now. Okay, all right. So we're going to count in, and

we're going to release the parachute, okay? Ready, everyone together.

Three, two, one.

Ooh. And there it goes.

Whoa.

Pull back.

It's very impressive.

It is, and it's very lightweight.

And so what's so unique about these parachutes is they weigh almost nothing,

they're incredibly strong.

And so for reference, the parachute that we used for Curiosity, it weighed only

about 100 pounds, but it actually had to withstand a total load on it of about

65 ,000 pounds of force.

Well, I love that, and it's a very interesting design.

But I still don't get what the fuss was stopping at Mars. We stop at Earth all

the time.

You've got some video here, actually, of what it was like to stop at Mars. You

were one of the lead engineers for this, the Mars Curiosity rover, which was

fantastic.

This is the size of a Volkswagen Beetle that's been coming into Mars'

atmosphere. Tell us what's happening here. At this point, we're at hypersonic

flow. We've slowed down to around 1 ,000 miles an hour, and then the parachute

deploys at Mach 2, two times the speed of sound, around 900 miles an hour.

It continues to slow down to subsonic speeds.

At that point, it's actually reached terminal velocity, so you can't go any

slower. So you basically cut the parachute away. Then the rover is in

descending towards the surface.

At this point, it turns on a total of eight main landing engines, eight

firing towards the ground to slow it down even further. And so that gets it

to around 200 miles an hour. As you approach the surface, we start something

very unique, which is called the sky crane maneuver. This is the first time

we've ever done this on Mars.

And what we do is we start to lower the rover on a series of three tethers.

we do this is we actually make the rover the actual landed platform.

And it allows us to have those big, powerful engines firing towards the

but at a safer distance away from the rover and away from the surface.

Those three tethers then cut away.

That little rocket ship flies off 45 degrees to the side, crash lands, its

mission is over, and now the rover is safely on the surface of Mars. Wow.

amazing.

I've ran down the coolest landing I have ever seen.

But this parachute, why does it have the gap?

It has the gap because it experiences something called a supersonic

So what you saw as it descended towards the ceiling was actually in subsonic

flow. So in subsonic flow, the parachute is relatively stable. But in supersonic

flow, things look entirely different.

And so we have a video that we can show you, which actually has the parachute

deploying at 2 .7.

Which is almost three times the speed of sound. And what you can see is that it

collapses and inflates like a jellyfish.

And so we don't want it to do that. But unfortunately on Mars, that's what it

does. And when that happens, you can actually cause the parachute to produce

less aerodynamic drag, which is what slows you down. It can actually damage

parachute and make it fall apart.

And so we were really concerned about this with the Curiosity rover because it

was the largest parachute we'd ever built. And it also was deploying at the

highest Mach number that we've ever deployed at. That is incredible. So the

allows it not to fall apart.

as it opens. This is absolutely fantastic.

Anita, I'm going to give you your parachute back because I think you might

to use it. Again, Anita, thank you to everybody.

So we can get there in one piece. We can stop using one of Anita's

incredible systems.

And then we're there.

And up on the screen now, you can see a picture.

of one of the places in Mars that I would like to visit. This is the very

beautiful... dappled uh center of victoria crater that crater uh is a real

picture it's 780 meters across it's been visited by the automatic rovers that

have been the really the pathfinder missions for our future human

and we've peered into that crater in its walls uh sedimentary rocks layered and

layers of rock that tell us about the history of mars there is still So much

left to explore, but we remain confident.

So much so that we've begun to think about the way we would get home from

Now, there's a way of lightening your packing load here by using what you've

all around you on Mars.

And that carbon dioxide, Mars' atmosphere, is about 99 % carbon

dioxide. And you can use that. It brings you some very important things, carbon

and oxygen.

And if you bring a little bit of hydrogen along with you, and it turns

that's quite easy to do, then you can make some useful materials with

called a Sabatier reaction.

Now, in a Sabatier reaction, you can combine hydrogen and carbon dioxide, and

the product is methane and oxygen.

And that is enough to make some rocket fuel. Now, you don't usually think of

methane as being something that can propel...

people and objects into space, so I'm going to show you.

Andy, goggle time. I think front row goggle time.

Good. All right. I know you think of methane as being a bit of a comedy gas

cows fart out, but actually, it can propel rockets.

Now, Andy's going to like this one, because there's a trick to it, and he

it has a more... He technically described it earlier on as a more flamey

So...

This is methane.

We are on our way home and there's just time for Tim

to say a final goodbye.

So it's been great talking to everybody.

at the Royal Institute Christmas Lectures from the International Space

I'm sorry I couldn't be with you in person, but I certainly think that I've

the most privileged position to be here on board at the moment and looking down

on the beautiful planet Earth. So to everybody back there, goodbye.

Thank you all for sharing in Tim's adventure.

But what you've seen here...

has been the adventure of our lives. These are the people who make not just

Tim's mission happen, but all of science happen.

This has been our adventure and it will be yours and yours and

yours and yours and yours. This is the adventure of your generation

and it's time you started it.

Thank you.

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