Space Dara O Briain's Science Club

Remember when being an astronaut sounded like

the greatest job in the world?

Riding a rocket into the stars!

Then you get older and you realise it's actually

sitting in a canister with two other guys, slowly floating.

In space, no-one can hear you scream

but you can certainly smell their farts for six months.

Tonight, we look at the difficult life of a spaceman.

I'm Dara O Briain. Welcome to Science Club.

MUSIC: "I Heard Wonders" by David Holmes

Hello, good evening, everyone, and welcome. This is our show

where we take apart a topic and look at it from many different angles.

We do this with some fantastic guests, no less than tonight,

ladies and gentlemen, our science gurus,

Astronomer Royal, Professor Martin Rees, thank you for joining us,

our reporters, Alok and Helen, thank you,

and our special guest, Josh Widdicombe. How are you?

Very excited to be here.

Delighted to hear it. And of course, in his den,

our resident material scientist, Professor Mark Miodownik.

Hello, Mark. Now, tonight on Science Club,

we're indulging our desire to expand our horizons,

cast away from Earth and find our place among the stars.

Science journalist Alok Jha goes talking to aliens

and asks, if we ever find intelligent life out there,

should we make contact or not?

It's quite possible that aliens could be

very highly competitive and aggressive.

Professor Mark Miodownik gets down to his underwear

to explore the very latest in spacesuit technology.

And special guest Josh Widdicombe goes to NASA

to find out whether he's got the right stuff.

LAUGHTER

Houston, I have a problem.

If you want to get involved with the show,

you can follow us on Twitter or visit the website.

Details on your screen.

But first, please welcome our special guest tonight,

probably one of the most eminent scientists alive today,

former president of the Royal Society

and the Astronomer Royal, Professor Martin Rees.

APPLAUSE AND CHEERING

-Hello, sir. How are you?

-Fine.

Let me quickly ask you about that title,

cos it precedes you to a certain extent, the Astronomer Royal.

Do you ever have to lug a telescope around to Buckingham Palace?

No, I don't. It's a job with no duties at all.

Wow! How did you get that gig? That's fantastic!

It's so exiguous I can do it posthumously,

-so I can keep going even after...

-Really? Congratulations! Very good.

Tell me about, we're talking about astronauts here.

It is a dirty, messy job being an astronaut.

It's a thankless job, would you say?

Well, I think to be the first one was great

but you know, when you're the 200th to go in the Space Station

and the only publicity is about whether the loo works

and things like that, it's not a great life.

No, and by the way, did you ever have any aspirations?

I think I'd have liked to be the first person up

and I think when I'm a bit older,

I'd be happy to go on a one-way trip to Mars.

Really? We'll come back to the issue of one-way trips at some stage.

Any further than Mars? Anything you'd particularly like to see?

Cos you've seen stuff through Hubble, obviously,

-you've seen enough stuff on telescopes?

-Yes.

Well, it's just the experience of looking back at the Earth.

I think, once you get beyond the Earth,

there's nothing as exciting as the Earth

and you can see it through a telescope, but it's the experience,

so there will be people who want to go on one-way tickets to Mars.

Yes, it is a delightful paradox

that the people who were most interested in the stars,

the first thing they'd do if they ever got there was turn around

and look back to Earth again.

That was true of the first people who got to the Moon, wasn't it?

They looked around and contrasted

the sterile moonscape with the beautiful, blue, fragile Earth.

And that was the iconic picture of the Earth

that we've all had on our walls for the last 40 years.

It does seem as if we may be a difficult moment.

We may have hit limitations in space travel.

It would be a tragedy to put these limits on space exploration

as it's very much the final chapter

in the story of mankind's defining need to explore,

a journey that goes back to our very beginnings.

It seems that we humans have a propensity for itchy feet,

ever since our ancestors strolled out of Africa 100,000 years ago

but it wasn't long before we realised that

having effective means and methods

are essential to proper exploration.

Around 400 BC,

the Greeks used a rudimentary knowledge of the stars to navigate.

Despite fears of sea monsters,

one even ventured to strange northern lands of beer drinkers

that turned out to be Britain.

Vikings appropriated wildlife to aid their exploration.

Ravens were deployed from boats to guide them to new lands

and the reward was the discovery of Iceland.

Wildlife-based navigation systems were rare, however.

Most explorers opted for stellar guidance.

Mediaeval Arabs refined navigation

with accurate star maps

and tools to chart their position

and the Chinese invented a portable magnetic compass.

But navigation still had a way to go.

In 1492, Columbus sailed the ocean blue

and discovered what he thought was the East Indies -

hence his insistence on calling the people who lived there Indians.

It took quite some time for anyone to realise

that they were, in fact, Americans.

Columbus's Indian faux pas

was largely because he had no idea

how far east or west he was.

Calculating that meant knowing the time,

which was impossible to do without reliable seagoing clocks

and they didn't arrive until the late 1700s.

With location finally sorted out,

others were adding another dimension to exploration.

In 1783, two French brothers

demonstrated their flying sheep experiment near Paris.

They believed that ovine aviation

was achieved by a special property of smoke they called levity.

It was soon decided that the fun shouldn't be restricted to ruminants

and man took to the air for the first time

but unfortunately, man had no control

over where the balloon was taking him.

American Samuel Langley realised that useful air travel meant power.

He had some success with rubber bands and steam

but more often than not, ended up

on the ground or in the river.

By the time powered flight was reliably in the bag,

most of the world had been explored.

Time for a new challenge

and a new destination.

In the 1920s, space pioneer Robert Goddard

invented liquid-fuelled rockets.

He even claimed a rocket could reach the Moon,

but not everyone was convinced.

The New York Times smugly pointed out that nothing can fly in a vacuum

and even though a series of cosmic dogs, astro monkeys and spacemen

suggested otherwise, it wasn't until the day after Apollo 11 launched

that the paper finally conceded

that a rocket can fly in a vacuum after all,

stating, "The Times regrets the error."

Even landing on the Moon hasn't satisfied our wanderlust.

We're roving on Mars,

probing Saturn

and voyaging beyond our solar system

but the irony is, WE are not actually doing the exploring.

We're now reliant on robots to be curious on our behalf.

Am I just too much in thrall to the romance of the Apollo missions

or is that like a sad anti-climax?

Well, I think it's inevitable

because as robots get better, the case for sending people gets weaker,

and I would say, speaking as a scientist and practical man,

there's no case whatever for sending people at all

but as a human being, as it were,

I'd like to feel that some people will walk on Mars

and go beyond, so it's an adventure, no practical purpose.

Do we learn more

because we've put, you know, we've put Hubble up,

we use it just as a laboratory that's remotely controlled?

Well, it's true, if we had a real geologist walking on Mars,

then probably, he or she would detect things

that the Curiosity probe won't detect

but if you add the huge extra cost of the person going there,

it's not justified, and robots are getting better all the time,

so I think there's no practical case for sending people.

No practical case, but obviously, it tugs at the heartstrings.

Sure, they'll go as explorers,

rather like crazy people go ballooning and things like that.

LAUGHTER

We do have a noble history, though,

we have, to a certain extent, conquered that environment.

We have walked on another planet.

I think it is wonderful that people have done

but we shouldn't kid ourselves

that there's anywhere as clement to live in

as the Antarctic or the top of Everest, so we're kidding ourselves

if we think it will be an escape from the Earth's problems.

Now, the issue of environment is vital to this, of course.

We have evolved to survive in this environment, rather than in space,

so when we go into space, we have to bring our environment with us,

whether in a capsule, or even more iconically, in the spacesuit.

But if you've ever wondered

what exactly, other than the astronaut, is inside the suit,

Mark has gone to find out.

'Ignition sequence starts.

'Five, four, three, two, one...'

Good evening. When astronauts leave the safe confines

of the International Space Station, they wear one of these.

It's called an Extravehicular Mobility Unit

but you know it and I know it as a spacesuit.

Since Neil Armstrong and Buzz Aldrin stepped out on the Moon in 1969,

the spacesuit has evolved

and I'm going to show you some of those changes

by taking off this suit bit by bit.

Spacesuits have all the systems

needed to protect astronauts from extreme temperatures,

micro-meteoroids and the void of outer space

but first and foremost, they need to breathe.

The air is supplied by the primary life-support system.

Back in the Apollo missions, that was a removable backpack

but here, it's fully integrated in the top half of the suit.

That makes it incredibly heavy.

That's why I'm attached to this hoist.

The air isn't just for breathing. It also inflates the suit.

This pressurisation provides protection

from the near-perfect vacuum.

'Roger, zero G and I feel fine.'

It stops bodily fluids from boiling

and turns a piece of clothing into a one-person spacecraft.

Now to get the suit off. First, the helmet.

I think I'm going to need a bit of help, though.

'The helmet fits onto the suit with a vitally important vacuum-proof seal.'

Thank you.

It comes with a distinctive gold-coated visor

to shield the eyes from unfiltered sunlight

but this has the downside

of making it hard to identify astronauts in photos.

Underneath the helmet is the communication cap

which contains the microphones and earpieces

that allow the astronaut to communicate with Mission Control.

It's often referred to as the Snoopy cap,

after the cartoon dog that looks similar,

and fond as I am of it, it's coming off now.

'Five, four, three...'

Thanks.

'..two, one...'

'Contact, 100%. Modulation is go.'

Most of the protection comes from the suit's hard upper torso and trousers.

In the 1960s, when very few people went into space,

astronauts were lucky enough to benefit from bespoke tailoring,

all-in-one suits made to measure.

But with the advent of the International Space Station

and the Space Shuttle, people had to share,

and spacesuits became modular,

allowing different-sized hands and legs to be screwed on.

There is one part of the suit that's still custom built - the gloves.

A mould of the astronaut's hands is taken to ensure a tight fit

and there's one additional component.

The fingertips feature battery-powered heaters

to stop the extremities from getting chilly -

something the Apollo astronauts had to do without.

Without the protective atmosphere of a planet,

astronauts needed to be shielded from the extreme cold and extreme heat.

And the suit does that with 12 layers of material,

but it's the silvery ones that do most of the work.

There's five aluminium-coated layers.

Now, these protect against solar and cosmic radiation.

This was the outer shell on the Mercury missions,

when the astronauts never left the spaceship,

but when they first ventured out in Gemini and Apollo,

there was the additional threat from high-speed micro-meteoroids,

meaning that one more layer was required.

Above all these layers is the iconic white shell.

It's made of Kevlar, Teflon and Gore-Tex

and it's extremely tough and fireproof.

Now you'll see why it takes so much training to be an astronaut -

just to get this thing off!

'All this insulation comes with the unexpected risk of overheating.

'Early astronauts came back drenched in sweat

'and condensation caused the visors to fog up,

'so it quickly became clear that a high-tech undergarment was required.'

I know, but it's comfier than it looks.

It's called a liquid cooling garment

and it was originally developed by the RAF

and then NASA took it and developed it for the Apollo space missions,

and what it does is channel water down little tubes around the body,

wicking the heat away.

'Beneath this, there was one final problem that had to be dealt with.'

Apollo astronauts had tubes and bags to remove waste.

But luckily, the International Space Station now has toilets.

You were proud, weren't you, putting it on?

-Is it really heavy?

-It's very, very heavy indeed.

If I hadn't been held up by a winch, I would have collapsed on the floor.

I mean, it's specifically designed to fight meteorites

and lack of air and the temperature and everything.

There are various myths about this.

If you floated off into space, if you got hit on the mask,

you'd instantly freeze.

You'd get very cold quite quickly,

but you wouldn't instantly freeze because there's no convection.

It's not like you swim in water and it draws the heat off your body.

Your blood is going to start to boil because of the reduced pressure and

then you are obviously going to asphyxiate quite quickly.

People think they might hold their breath

but then your lungs just explode.

Which is a bad thing, so you have to breathe out while thinking,

"This will be my last breath unless someone captures me,"

in Douglas Adams style.

The temperature at which things boil dramatically decreases.

What happens is that your vapour pressure...the temperature

of the vapour pressure goes down, so things start quickly boiling.

The latent heat of that freezes you, so you get very cold,

very quickly.

-But you're dead at that stage anyway.

-You're dead at that stage.

-You've boiled yourself to death. Can we see?

-Let's have a go.

If we get some water we'll try and make some fake blood.

Can I just borrow that little bit of water there if you don't mind.

Thank you very much. Just a little bit.

I am going to put a little bit of food colouring in this

and this will change the boiling temperature of it slightly.

-Yeah. Especially that much!

-I don't use food colouring very often.

OK, well, I have very thick blood, all right? Would that pass?

-Are you happy with that?

-Fine. That's some blood in your veins.

So now, you are fine, you are in your spacesuit, but,

suddenly your spacesuit fails, you exposed to the vacuum of space!

Which we'll now recreate. This is quite dramatic.

Don't look away, because it happens relatively quickly.

This is pumping air out of the bottom here, it's coming out there.

That cloud is the vapour condensing into a cloud,

it's been sucked out too.

-You see the pressure here.

-The pressure is dropping very quickly.

And you can see a froth, so now it's starting to froth and oh, yes,

that's probably the moment at which you aren't feeling very well.

LAUGHTER

Because presumably your eyes have done this as well,

all the fluid in your body, the brain?

The fluids are doing this, yes, that's the big problem.

I think it's worth seeing that again.

This is the blood boiling moment once again. Wow! That's dramatic.

We are essentially saying that bit at the end of Total Recall,

where he's thrashing around the planet of Mars and his eyes expand.

That's scientifically accurate.

You'd expand. You would expand, actually.

People who experienced very low vacuums show their hands

and limbs do get very much bigger.

Can I just stop this

and take this out for the sake of calming down that noise?

Lovely. Good stuff. I want to show you something else.

This is genuinely astonishing.

Space travel is just one long engineering challenge after

another and one thing that fascinates me is

the possibility of humans travelling out beyond the solar system,

maybe to populate another planet in another solar system.

I'm not the only person who has imagined this.

We've this giant blow-up here of one of the most astonishing

documents I have ever seen.

It's the Rockwell Integrated Space Plan written by a man called

Ronald Jones and is basically a step-by-step flowchart of what

we'd need to invent in order to get to a point...I mean,

it's difficult...we start here in the '80s,

really where we were,

first-generation reusable spacecraft.

The American space shuttle Challenger, Columbia, Discovery.

Down here...that's 1883...down here to 2100 which is human

expansion into the cosmos begins.

LAUGHTER

It's full of cool phrases like that the entire way through.

The only thing obviously it's slightly optimistic.

This made sense - the US International Space Station Project,

but that's happened a couple of times now, back in the mid '90s.

By the time we get to where we are here 2008-2012 we see

the International Lunar Base has expanded,

the outpost is there and the Moon Port,

that seems a little bit further afield than 2014.

-Have you been examining this?

-There's some weird stuff.

-They start a shop here. I don't know why they need to shop.

-A shop!

There's obviously going to be a shop to sell Mars bars

and merchandise and T-shirts of I Live On The Moon Post.

How do you think we're going to fund the rest of this if the DVD sales

don't work out?

Unlimited safe solar energy for Earth? Create new

moons for Mars, if required.

-They'll always be required.

-Who doesn't need more new moons?

This is the kind of ambition we've lost, you know.

The only thing really missing from here is a space elevator,

if you ask me, because I think actually that's a far better

way to spend this kind of ambition but you know,

we just need a bit more of this and I think it should be made

into wallpaper and papered on every child's bedroom across the globe.

Yeah! Forget princess wallpaper and things like that.

One day we'll go, "Put this up", and depress them.

This massive flowchart.

Yes, maybe we stalled there

but there are still people who are hoping to make this a reality.

My friend Josh Widdicombe has been off to Houston, Texas,

the home of NASA, to investigate.

When I was growing up I thought space travel was really exciting.

We'd been to the moon, what next? Are we going to Mars?

Are we going beyond Mars? Are we all going to end up living in space?

This hasn't happened, has it? And I want to know why not.

I want to know what's the future for human space travel.

So I've come to its spiritual home - Houston, Texas, to talk to

the people who are busy trying to get humans into space.

Physicist Paul Davies, has published a manifesto for a manned mission

to Mars.

If I am honest with you, it's a little out there.

I think the only way we're going to be able to afford to go to

Mars is a one-way mission.

I think if Mars is such a great place to go,

leave the astronauts there. They can do some fantastic work, they can...

If they're scientists they can do some good science.

-You're looking sceptical.

-I'm not signing up.

This isn't a suicide mission, I should explain.

You're not saying to four people, "Right, you've got enough

"oxygen for three weeks. After that, tough."

What you are saying is you are going to be establishing

base camp for a new permanent human presence on the Red Planet.

We'll send the sandwiches and the letters from home and the equivalent

and eventually other colonists will arrive and join you.

-Would you do it yourself?

-I'd love to go, but my wife won't let me.

How very convenient!

I must admit I don't get why Mars has to be a one-way mission.

So I'm going to meet a rocket expert, Eric Davis, to see

if we can't just make it a round trip.

-Hello.

-How are you doing?

'At the moment, we go into space using chemically propelled rockets.

'Eric says they're going to be no good for getting us to Mars.

'Apparently, it all comes down to something called

'the rocket equation.'

Basically, the change in velocity is equal to the exhaust velocity

-times the natural log of...

-'I'm not going to lie, I'm lost already.

'Luckily, Eric has got an easier way to explain it.'

-Eric, I'm ready.

-Here's your rocket propulsion.

'OK, it's not the perfect analogy, but imagine I'm a spacecraft

'and this fire extinguisher is my fuel tank.'

Five, four, three,

two, one...

MUSIC: "2001 - A Space Odyssey" by Alex North

Houston, we have a problem.

'What Eric's trying to tell me is that to get to Mars with chemical

'propulsion, so much of your spacecraft would have to be fuel,

'a whopping 95% - that to build a rocket with enough fuel to get

'there and back would be completely impractical.'

So how does it exactly work?

A nuclear thermal rocket is basically atomic fission.

It's the fissioning of uranium atoms in a hot core.

The core heats up from the nuclear radiation

and you are going to pass liquid fuel through.

It gets heated up and gets expelled out the rocket engine.

The rocket goes very fast.

When do you think we're going to be launching this mission to Mars?

We could do nuclear rocket engines at any time.

It's just a matter of whether there's the political will

and the money devoted to making it happen.

'So it sounds like we've got the technology almost sorted.

'But what about us?

'How do we know that humans could actually survive

'these long space missions?

'Here in Galveston, Texas, NASA are trying to find out by paying

'people to stay in bed.'

Apparently, lying horizontal for weeks at a time mimics

the effect of zero gravity on the body, allowing scientists to

monitor one of the biggest problems with hanging out in space -

the gradual weakening of bone and muscle.

Dirk has been at it for two weeks. Luckily, he's only got 57 days to go.

-Hello.

-Hey.

-How is it going? I'm Josh.

-I'm Dirk.

-Nice to meet you.

-You can't get up, obviously.

-No, no. I am stuck here.

Let's cut to the big question. How do you go to the bathroom?

That's the hardest thing to get used to.

You have to do everything from the bed

and they collect all of your urine and, of course, use a bedpan.

So that's the hardest part of this, I think.

To combat the problem of withering muscle and bone

they've created this monster.

OK. What's happening here?

'This is a vertical treadmill' -

'the Earth equivalent of what astronauts

'use to stay healthy in space.'

I don't like this at all.

'Basically, this kind of exercise keeps astronauts' bones healthy

'on long missions by providing enough resistance for a proper workout.'

Tell my family I love them.

Let's do this.

All right, Josh, here we go.

You're going to start at two miles an hour in three, two, one.

-I like the way...oh, my God, that's fast. Is that two miles an hour?

-Yes.

It feels like I am really making progress towards the ceiling.

-It's all right. You want to go a little faster?

-Why not?

-I'm only going to get to do this once.

-Here we go,

three miles an hour.

That is...it's a real jog. I reckon I can do four.

All right, let's give four a shot. Here we go.

-Three, two, one, four miles an hour.

-Yeah, I can't do four.

In deep space, you'd have to do two hours of exercise a day.

I can barely last ten minutes on this, which makes me wonder what

kind of person actually has what it takes to do this for real?

I think it's finally time to meet an astronaut!

'Andy Thomas has been in space four times.'

Pleasure to meet you.

'He's spent 130 days on the Mir Space Station and he was on the first

'flight back into space after the Columbia disaster in 2003.

'I asked him

'whether he thinks we should be really trying to get to Mars?'

Can you imagine anything more mind blowing than walking on Mars?

-No.

-Everything is a different planet,

the physics is different and nature behaves differently

and you are on this ancient, windswept surface.

I think that would be just a wonderful experience.

If we get to Mars, can you imagine that we'll be living there?

There'll be people born on Mars.

I think ultimately you'll get to that point. That's colonisation.

That will happen but it's a long way off, probably 100 years away.

One day we'll have some kind of technical breakthrough that

will develop an improved propulsion system

and that will open up the solar system.

Do you think that's a serious proposition?

Yes, eventually, it's not a question of if, but when, I'm sure.

There you go. You heard it from an astronaut.

In just 100 years' time, my great-grandchildren

and your great-grandchildren could well be Martians.

Please welcome to this sofa Josh Widdicombe

and another special guest, Dr Iya Whiteley,

the Deputy Director of the Centre For Space Medicine at UCL.

There's a number of questions from that. Congratulations.

You look like some weird meat puppet being extended from the ceiling.

The astronaut got excited talking about the different

physics on Mars. There isn't a different physics on Mars

-per se, is there?

-Different geology, but not physics.

-OK, grand.

It's not suddenly "up is down and down is up" when you get to Mars.

It's just red, more red. Were you disheartened?

No, I came home inspired. Not to go to Mars.

You could see what I would achieve there, but no,

I went there thinking it was a kind of non-starter, not going to happen.

Certainly talking to Andy the astronaut, you suddenly go,

these are people that are in the industry that say

this is going to happen.

It's almost less the technological problems than the political ones.

Not backing it financially.

It's an enormous project financially, in terms

of resources, that amount of fuel and everything to draw together.

The Apollo programme was done to beat the Russians, not for science

and the question is, will anyone do it for that motive?

I would guess the Chinese might, they might feel they want to leapfrog what

the Americans did and send people to Mars and they could do if they tried.

Apart from that, I don't really see anyone's got the motive to

spend the money until it becomes much cheaper.

Until then, we're discussing possibly going, but not coming back.

This changes everything to a certain extent.

Iya, you deal with the medical side of this.

For someone to take a journey of that length of time

away from Earth, psychologically, what would the effects of that be?

One factor is actually being bored really, because it's a long journey.

So when we're actually coming back, the issue is that you've achieved

the greatest thing in your career, your dreams and probably the

first person to step on Mars

and now you have to travel over a year back.

Really, these people have to be quite motivated

when they come back on Earth.

Maybe a year and a half of comedown

from the euphoria of having reached Mars?

Also having to spend that amount of time with what

are essentially work colleagues must be the most annoying thing.

It's always going to be confined spaces - a tight,

enclosed environment.

One of the things of the shock

when people come up to international space stations is the air.

It has all the bodily human smells that you wouldn't want to

come across in a gym changing room.

When they get the resupply ship, and, for example,

it comes with goods, and they will open it

and people just gather around

because they get this woof of air of fresh food.

I know a story from the Russian cosmonauts that they when they packed

they packed in pickled, well, salted cucumbers,

and they put them in the suit.

So when they got to the space station and they opened the suit,

the smell was released and they really like that smell.

It reminds you of home.

Cucumber? It wouldn't remind me of my home. It's not my thing.

-Does this make you even less...?

-Yeah.

I met Andy - the astronaut that I met - his wife is an astronaut

and you're not allowed to go into space with your spouse.

That is not allowed.

I think NASA's feeling about that was that if there is a disaster,

they don't wish to orphan the family.

-It's not that they'd bicker?

-No.

One of my favourite theories is that of Professor Samuel Lepkovsky -

he was a professor of poultry husbandry

in Berkeley University, California -

who suggested that we would save weight by sending really fat people,

because really fat people could survive on their own reserves of fat

for up to 90 days

and that would save you packing food.

-This is the...

-They are packing food.

They already had begun the process of packing food some time before it.

Still to come on the show, Mark tests a brand-new rocket fuel

and Helen Czerski goes on the hunt to find

an invisible cosmic killer.

And Alok asks whether we should communicate with aliens.

APPLAUSE

One of the requirements

if you are going to travel into deep space

will be to make your own tools, make your own equipment,

for which you need this - the much vaunted 3D printer.

And it doesn't disappoint. This thing will make 3D objects.

You model them in the computer, in a CAD file.

You press "print" and out comes the object.

And it really could be revolutionary.

This could be the third industrial revolution.

But in the context of space, you're out there

and need to make all sorts of objects.

A nozzle might break or you might need a new replacement cog.

You programme it in - all the parts will be in CAD file with you,

or mission control would send them to you -

you press "print" and out it comes.

Give me an example of something that's been built.

This isn't the first thing you'd need to be able to build,

but what this illustrates is that's a 3D object

that came out of this printer - it started as a CAD file.

The other thing is, it's giant,

but you can change the size of things by clicking a button.

It's all about individualisation.

So rather than creating expensive moulds and getting the sizings...

Are you opening a merchandising stall? Is that what you're doing?

And in case you're wondering if you can only make very basic objects,

you can actually make stuff with moving parts, cogs.

-Like replacement hips? Replacement teeth?

-Yep.

All these things. So you could medically prolong your own life.

That's another thing. In space, the future of body parts...

People are talking about producing scaffolds to create new organs.

It is revolutionary. It's only going to get more exciting.

It's like in the 1980s, when personal computers were just starting up.

It is possible that everyone will have

one of these in their houses in the future.

Instead of buying stuff from shops, you just buy the information

and you press print.

What are we making today? What's it going to create?

It's important to have sport when you're on another planet.

Not just useful objects.

While you are waiting for something to break,

we're printing a sporting object which I will tell you of later.

If you want to see some of the miraculous medical uses

of a 3D printer, go to our website where there's a fantastic report.

We'll be back and see the results of this. I'm excited.

I've wanted to see one of these for ages.

We've been to-ing and fro-ing into near space for 50-odd years.

Only recently, we've begun to understand the dangers

we literally didn't see coming.

Helen Czerski reports on a fascinating scientific mystery.

During the Apollo missions,

humans travelled further from Earth than ever before.

They made history. They walked on the moon.

Saw unprecedented views of our planet.

But they also reported something very strange.

They saw mysterious white flashes when their eyes were closed.

Mission control was so concerned they asked the astronauts

to record every flash.

They weren't sure but they had a hunch that they were caused by

a kind of radiation originating from outer space called cosmic rays.

Cosmic rays are charged particles travelling extremely quickly

through interstellar space.

They can be really damaging to living tissue.

But down here on Earth we're protected

because the Earth's magnetic field acts as a shield.

For the Apollo 16 mission, NASA developed a special device

to find out if cosmic rays were causing the flashes.

A helmet that could detect the energy levels of single particles.

The astronauts ran several tests with it and the results were conclusive -

cosmic rays from deep space were indeed penetrating

the astronauts' eyes and interfering with the cells

on the back of the retina.

And that led to a question.

If a single particle could produce an effect you could see,

what else were these particles doing to the tissues of the body?

The biggest fear was that the high levels of cosmic radiation

that exist in deep space would lead to cancer.

'So to understand the risks,

'NASA established a space radiation laboratory

'here at Brookhaven National Laboratory in Long Island.

'Frank Cucinotta, who heads up NASA's programme here,

'has come to show me around.'

OK, so this is the computer control system.

'Highly charged particles are so dangerous

'I'm not allowed inside the radiation chamber.

'But what they do here is fire a beam of particles

'at human and animal tissues, like lung, stomach and brain -

'the soft tissues most vulnerable to cancers -

'to find out what kind of damage cosmic rays cause.

'And whether there's such a thing as a safe dose for humans.'

-MESSAGE:

-Attention. Attention. Beam is evident.

'What they're finding is that cosmic ray damage is different to

'any other form of radiation we've ever come across.'

We're looking at images of brain cells where the blue colour

indicates the nucleus of the brain cell and the green colour shows you

a wake of DNA damage that's been caused by the ion particle.

What's striking is that a single cosmic ray has come right the way

through these two nuclei and caused a really strong trail of damage.

But if it had been an X-ray, it might just have caused

one spot on one of these nuclei.

So as far as radiation goes, a cosmic ray has much more bang for its buck.

Yeah, it's much more of a concern. It's a qualitative difference.

'The reason cosmic rays are so damaging,

'is because they're thought to originate

'in some of the most energetic events in the universe -

'supernova explosions.

'Where charged particles are accelerating close to

'the speed of light and spat out into the cosmos.

'Frank's team has shown that just one of these particles

'has the power to charge through human tissue,

'strip molecules of electrons and physically break the DNA -

'potentially leading to cell mutations and cancer.

'So far, we've seen astronauts with the highest levels of exposure

'develop early cataracts because the soft tissue of the eye

'is most vulnerable to damage.

'The current thinking is that on a mission to Mars,

'the change of developing terminal cancer could be as high as 30%.

'I asked Frank what the solutions are.'

We have some good strategies.

The first one would be shielding spacecraft

by changing the composition of the walls,

the thickness of the walls of the spacecraft.

Water and polyethylene seem to be the best shielding materials.

The second one is the knowledge of the solar cycle.

We know that cosmic ray intensity is higher at the part

of the 11-year solar cycle called solar minimum.

So if we stay away from solar minimum,

we can reduce the exposures.

The last way is the person themself.

As we learn more about genetic factors,

we'll be able to find attributes that make a person more resistant

and more eligible for a long space mission.

When it comes to future space exploration,

rocket technology clearly isn't the only challenge.

Because until we can protect ourselves from cosmic radiation

in deep space, we may not be going anywhere.

This is a phenomena we've noticed from the earliest space flights?

Yeah, it is really weird because it was seen very early on

and everyone forgot about it.

We've had sci-fi things

and we're very familiar with the idea of humans in space.

No-one ever mentions this, so it's a secret hidden in plain view.

Yet it is the most common effect, because it's constantly with us.

Once you get past, is it the magnetic field

of the Earth that shields us from this?

It's our great shield.

That's why we can have life wandering about on the surface

of our planet.

It might survive under the oceans if we didn't have a magnetic field

but up where we are, we need that shield

because we would be damaged too quickly.

And there's no chance of building a magnetic field that would surround

a ship as it travelled to Mars or, indeed, a bio dome when on Mars?

Well, a very thick lead shielding would do the job but obviously

to get that into orbit's even harder.

It's not feasible to shield against.

Is this the one clear limiting factor on how far we can travel?

I think it probably is for humans.

Until we can deal with this or get a medical solution.

It is yet another reason why humans will never go much beyond Mars,

even if that far.

And is there any way in which this man who suggested

that only fat people go into space,

that their layers of fat would in some way

deflect, absorb or somehow...?

It's true, because fat is largely water

and water is one of the best materials for absorbing these things.

The tubbies are coming out as the champions of this.

It's wishful thinking. You want to volunteer, don't you?

Don't keep bringing it back to me. I don't know why you're saying that?!

Just got zinged by the Astronomer Royal.

Um, OK.

OK, so what do you actually need to bring with you just to make

that short hop to the Moon? Let's have a look at the data.

The Moon is on average:

To get there you need a ship capable of escaping

the Earth's gravity and some astronauts made of the right stuff.

..men and women applied to be astronauts

for the American space programme

but selection was strict - both physically and mentally.

The successful Apollo candidates were, on average:

Plus they were clever, with an average IQ of...

Three of the 32 serving astronauts

were selected for the first trip to the Moon.

Amongst their luggage were medical supplies,

survival gear

and food supplies.

This is the '60s, remember.

But the biggest problem isn't the dodgy cuisine,

it's the escaping Earth's gravity.

And for a big problem, you need a big rocket.

The Saturn V was a monster.

It consisted of three stages.

First, five F1 engines launched the astronauts.

The most powerful of their time,

together they produced 160 million horsepower.

They burned for 165 seconds and carried the craft 68km.

A modern family car allows 65mpg.

Five F1s do about 13cm.

The second stage takes the spacecraft a further 106km.

And the third stage takes the craft into orbit.

And on its way to the Moon.

Guided by a computer with less power than your average wristwatch.

The astronauts spent...

..together in a metal can.

Just two hours and 32 minutes of which was actually on the Moon.

They splashed down in the Pacific Ocean considerably lighter than

when they set off.

They arrived to a heroes' welcome and three weeks in quarantine.

It's enormously complicated when we go anywhere in space.

The huge complication is escaping the gravitational pull of Earth.

-It is.

-You need quite a kick to get off here.

Many people thought it was impossible.

Until liquid fuel rockets came along and people thought,

"My God, those are powerful!

"They really might get us to the Moon."

And so, um, what I thought we'd have a go at,

is seeing quite how easy it is to make a rocket.

Once you get the hang of the fact

that liquids have a huge high density of energy in them.

If you can release that by reacting with an oxidation agent like oxygen

in the air, it's really surprising.

The liquid we are using for this is Eastern European vodka.

How strong a concentration have you got?

We've searched high and wide

to find one that's even stronger than last week's show

and found one that's 96.5% alcohol.

This is not so much a drink as a rocket fuel, we think.

-Let's try that.

-Where is it from?

-Is it actually genuinely Polish?

-Yes, it is.

There's debate online over the fact

that we've claimed various Russian and Balkan vodkas to be -

-But this is actually Polish.

-All vodkas, essentially, are Polish.

-Except that everyone else is making them.

-You're right. OK. Grand.

I'm not going to step on your heritage at this point!

I mean, this is essentially pure ethanol,

and if we put this into a bottle like this,

it's going to mix with some oxygen,

and they will combust.

Now, we're not just going to fire it willy-nilly.

We have a path for this, by the way.

I know. It's health and safety gone mad,

that we're not just going to fire rockets at our audience(!)

Rockets work on...

It's Newton's Laws, which is basically, you know,

the fuel goes that way, so the rocket goes that way.

-It's action and reaction.

-It is action and reaction.

So you're creating a hot, pressurised gas.

That goes that way, and that means

it has to push something that way, and that's your rocket.

The great thing about these liquid fuels

is that they have a huge amount of bang for the mass.

That's the big trick for getting off the planet.

-I'm ready. Can we have a three, two, one, countdown?

-Yeah.

Five, four, three...

AUIDENCE JOINS IN ..two, one.

ROCKET POPS

LAUGHTER

See? I mean, as well, if you're going to have a cameraman

standing directly in line with the rocket...

Yeah, see, I want to see THAT in slow motion!

This guy being hit by a rocket!

Let's see it in slow motion!

LAUGHTER

Yeah, let's try it again,

but with you a foot back, if we can.

Let's have a countdown.

ALL: Five, four, three, two, one.

ROCKET WHOOSHES

APPLAUSE AND CHEERING

Very happy with the escape velocity,

very happy that it returned back down to earth.

Let's have a look at it in slow motion.

Let's have a look and see what it looked like.

OK, ooh, look at that!

And it returned safely down.

-Very good. Loving that!

-APPLAUSE

Wow!

This is a doddle, this business!

OK, if you've any questions about space travel

or any ideas you want to chat about,

we have our After Hours Science Club,

where an expert in space exploration

is waiting to answer your questions.

Just go to the website to get involved,

or join the conversation on Twitter.

APPLAUSE

Professor Rees, every week we ask our esteemed science guests

to nominate somebody for our Hall Of Fame.

Generally, a scientific figure from history

who has been slightly overlooked.

Who would you like to put into the Hall Of Fame?

My choice is really not so much a scientist

as a science-fiction writer.

Someone called Olaf Stapledon.

He was actually a lecturer in philosophy at Liverpool,

but he wrote, in the 1930s, two classic science fiction books.

One was called Last And First Men,

and he also wrote another book called Star Maker.

And Star Maker is a sort of God who creates universes,

and it's really the first description of the multiverse.

So he's an amazingly imaginative person who wrote these books.

They influenced, in particular,

Arthur C Clarke and Maynard Smith,

the great biologist.

And, moreover, I do like to tell my students

that it's better to read first-rate science fiction

than second-rate science. DARA LAUGHS

It's much more interesting, and no more likely to be wrong.

Fantastic! OK. I genuinely banked somebody in here,

obviously my first choice would be Samuel Lepkovsky.

The man who said fat people should go into space.

But, amazingly, we have no photographs of him.

It is strange(!) So instead, I'm nominating this man.

Cosmonaut Gherman Titov.

He has a lot of firsts to his name.

He is the first man to spend a day in space,

the first man to sleep in space,

first man to take a photograph of the planet from space.

So all these firsts. Really, the one he's remembered for

is that he's the first man to suffer from space sickness,

which is an exaggerated form of air sickness or seasickness,

caused by the fact that all of your reference points, visually,

are upside down, while you feel right-side-up.

It's quite horrendous, and affects people quite badly.

So that's poor old Gherman Titov. He goes there on the wall.

Exploration is not just about us heading off into deep space.

From the comfort of home, we've been scanning the skies

to see if anything is out there trying to find us.

And, of course, we'd be privileged and awed

to discover intelligent life elsewhere in the universe.

What a momentous event that would be! Or WOULD it?

They're still out there, sending back signals from 15 billion miles away.

Voyager 1 is now the furthest man-made object from Earth,

and is, at any moment, going to leave the solar system.

And Voyager 2 isn't far behind.

On board each probe is a golden record

containing a greeting from Earth and information about humanity,

should the probes be intercepted by intelligent alien life.

But should we seek out alien contact anyway?

What if all ET's interested in is wiping us out?

Before we even begin to look for ET,

it might actually be instructive

to take a look at life on Earth from an evolutionary perspective.

One of the nice things about biology,

and evolution, for that matter,

is that from really rather different starting positions in,

if you like, the tree of life,

again and again, the same sort of solution arises.

So here we are on Steve's stall, and we have the octopus.

And the fascinating thing about this creature is, at first,

it looks remarkably alien, but let's look a little bit more closely.

In particular, let's look at the eyes.

These eyes, it turns out,

are constructed in effectively the identical way to our eyes.

They are known as the camera eye.

And this gives me some confidence to start with

that the alien will have not only eyes,

but for various reasons,

we can be confident it will be a camera-like eye.

But the camera-like eye in the octopus has evolved

completely independently of the camera eye in ourselves.

'If sophisticated eyes have evolved separately more than once,

'then what about intelligence?'

If we look at the way in which brains evolve,

we see that not only have they become independently large

in basically unrelated groups -

parrots, crows, various sorts of ape,

even the octopus, it so happens -

but in each case, their cognitive world

is surprisingly similar to ours.

It does suggest that, if you like,

thinking's going to be the same, wherever you are in the galaxy.

Now this is, of course, guesswork, to some extent.

Of course it's guesswork, because we only have one Earth,

one biosphere, so far as we know, a single origin of life.

In fact, many astrobiologists believe

that we'll detect life on other worlds

within the next few decades.

And it's probably reasonable to assume that natural selection

as an evolutionary driver, is a universal principle,

that will be at work wherever there's life in the cosmos.

So it follows that intelligence, if the conditions are right,

will exist on some remote world.

In California,

at the Search For Extraterrestrial Intelligence Institute,

senior astronomer Seth Shostak

is leading the search further out in the galaxy.

It's nice to see you.

BEAM-ME-UP NOISE

Seth, how convinced are you that intelligent life

exists out there somewhere?

All we can say is, yes, we haven't found ET yet.

I remain optimistic that that might happen

in the next couple of decades.

But if this is the only place, even in our galaxy,

where there's not just life,

but life that's fairly clever,

then that makes us a miracle.

And, you know, after looking at 500 years of astronomical history,

I'm disinclined to believe in miracles.

The thing is, our history on Earth is littered with episodes of contact

between intelligent civilisations

that were essentially alien to one another.

And more often than not, it's ended badly for one of the cultures.

The more technologically advanced usually triumphs.

Violence is depressingly common.

But who's to say that aliens would be as aggressive as people anyway?

It's quite possible that aliens could be

very highly competitive and aggressive,

and unlike many Americans, I firmly endorse the theory of evolution,

and there IS a survival of the fittest.

But what happens as you move up the scale,

the definition of the "fittest" can change.

Tell me a bit more about that.

Remember, they had to survive for possibly many millions of years,

and you can't do that in a state of perpetual conflict.

From what I can tell,

from political science, sociology, and psychology,

we're shifting in the direction

of more peaceable, pro-social kinds of behaviours.

There are billions of stars out there,

and probably an even bigger number of planets.

It's not unreasonable to expect that some form of alien life IS out there.

The chances of us finding them,

or them finding us, are actually very small.

And even if contact was made, any conversation would be painfully slow.

So, should we be afraid of aliens?

Well, human beings have always been curious

about the world and the universe,

and that curiosity has led us to some of our greatest advances.

It strikes me that, if we found evidence of alien life,

why would we not want to contact them?

Explorers launch into the unknown.

We deal with the consequences later.

SENSOR BEEPS

APPLAUSE

So, Alok, fresh from killing the pandas last week,

this week you want to kill ET as well.

Is this really our choice anyway? Whether we communicate with aliens?

There's two points here. One is, why wouldn't you?

I mean, wouldn't you want to?

It just seems a really strange thing to do,

to know that there's intelligent life out there, or even A life,

and think, "You know what, let's just not bother."

The second thing I think's interesting is,

and a big-up here to Charles Darwin, of course,

the idea of evolution by natural selection,

the idea that it is the thing that we expect will happen.

It doesn't matter what these chemicals you start with.

We can pretty much guess intelligently

what these life forms might do, how they might behave.

I think it's magnificent proof that,

actually, he had such a great idea back then.

We already know how to search for exoplanets.

We have Kepler out there searching all the time.

We also know what to look for,

what are the tell-tale signs of there being life on the planet.

Well, it's very exciting, because until 15 years ago,

we didn't know anything about planets around other stars.

Now we know that most stars have planets around them,

many planets, like the Earth.

So lots of possible sites for life to develop.

We don't yet know if there is life in any of those planets,

but in 10-20 years, I think,

by observing these planets carefully,

we'll be able to see

if they've got oxygen and things like that.

But also, I think we mustn't be too anthropocentric,

because, despite what Simon Morris says,

it could be there's another kind of life

based on quite different chemistry

and it could be, of course,

that it's much more advanced than us.

Because, after all, we are just a stage in life on Earth.

In the future, there's going to be different kinds of life,

either genetically modified versions of humans, or maybe machines.

And anything out there may be at this more advanced stage.

So I think we should be very open-minded about what we look for.

Are you confident that there is alien life?

No. I mean, I think we can't bet, because we don't know

how likely it was for life to get started here on the Earth.

We don't understand that.

That's a basic problem for all biologists,

and we don't know how it would evolve.

But I think it's worth the search.

Also, I think it would be great to find any evidence of life,

but also, of course, if it's not there,

then that has an upside too,

because we can then be less cosmically modest.

We can say that, even though

the Earth is a tiny speck in this huge cosmos,

it could be the only place in the galaxy where life has evolved.

-By the way...

-PLANE ROARS OUTSIDE STUDIO

Oh, we'll wait until the giant, low-flying plane passes overhead!

Man, it would be ironic

if an alien invasion started just as we were sitting here discussing it!

I would laugh if we were all marched into slavery by our alien overlords!

Let's see how our 3D printer has done.

Mark, do you have the result of that there?

Yeah, hold on. I'll bring it over.

Lovely stuff.

Now, this may seem tiny and incidental and unimpressive,

but nonetheless, printed during the run of the show,

maybe started a little bit beforehand.

It is what you would need on the moon, which is, of course,

a Science Club...

what is this, exactly?

-LAUGHTER

-It's a Frisbee!

I thought it was a coaster!

With all of this technology, to build a drinks holder!

In space, if you throw a Frisbee and fail to catch it, it's gone.

It's off into the next galaxy. You have to print another one.

Thank you very much for that, Mark Miodownik,

as well as reporters, Dr Helen Czerski and Alok Jha,

and Josh Widdicombe, of course, who came with Dr Iya Whiteley,

and our major guest tonight, please thank Prof Martin Rees.

APPLAUSE

But what can we take from tonight?

In the old days, to become an astronaut,

you had to have the "right stuff",

Fighter pilot, square-jawed, all-American hero.

It turns out, what we actually need are astronauts who are old,

don't mind the smell of poo, have no real reason to come home again,

but most of all, are fat enough

to live without food for three months at a time.

The door's open to all of us!

From everybody here at Science Club, goodnight.

APPLAUSE

# And I'm floating like God in his heaven

# High in the stratosphere

# Don't come quick, you can see our house from here... #

Subtitles by Red Bee Media Ltd

# Floating like God in his heaven. #