0:00:02 > 0:00:04Remember when being an astronaut sounded like
0:00:04 > 0:00:05the greatest job in the world?
0:00:05 > 0:00:06Riding a rocket into the stars!
0:00:06 > 0:00:09Then you get older and you realise it's actually
0:00:09 > 0:00:12sitting in a canister with two other guys, slowly floating.
0:00:12 > 0:00:14In space, no-one can hear you scream
0:00:14 > 0:00:16but you can certainly smell their farts for six months.
0:00:16 > 0:00:19Tonight, we look at the difficult life of a spaceman.
0:00:19 > 0:00:22I'm Dara O Briain. Welcome to Science Club.
0:00:24 > 0:00:27MUSIC: "I Heard Wonders" by David Holmes
0:00:46 > 0:00:49Hello, good evening, everyone, and welcome. This is our show
0:00:49 > 0:00:52where we take apart a topic and look at it from many different angles.
0:00:52 > 0:00:55We do this with some fantastic guests, no less than tonight,
0:00:55 > 0:00:57ladies and gentlemen, our science gurus,
0:00:57 > 0:01:00Astronomer Royal, Professor Martin Rees, thank you for joining us,
0:01:00 > 0:01:02our reporters, Alok and Helen, thank you,
0:01:02 > 0:01:05and our special guest, Josh Widdicombe. How are you?
0:01:05 > 0:01:06Very excited to be here.
0:01:06 > 0:01:09Delighted to hear it. And of course, in his den,
0:01:09 > 0:01:12our resident material scientist, Professor Mark Miodownik.
0:01:12 > 0:01:14Hello, Mark. Now, tonight on Science Club,
0:01:14 > 0:01:17we're indulging our desire to expand our horizons,
0:01:17 > 0:01:21cast away from Earth and find our place among the stars.
0:01:23 > 0:01:26Science journalist Alok Jha goes talking to aliens
0:01:26 > 0:01:29and asks, if we ever find intelligent life out there,
0:01:29 > 0:01:32should we make contact or not?
0:01:32 > 0:01:35It's quite possible that aliens could be
0:01:35 > 0:01:37very highly competitive and aggressive.
0:01:37 > 0:01:40Professor Mark Miodownik gets down to his underwear
0:01:40 > 0:01:43to explore the very latest in spacesuit technology.
0:01:43 > 0:01:46And special guest Josh Widdicombe goes to NASA
0:01:46 > 0:01:49to find out whether he's got the right stuff.
0:01:49 > 0:01:50LAUGHTER
0:01:50 > 0:01:52Houston, I have a problem.
0:01:52 > 0:01:54If you want to get involved with the show,
0:01:54 > 0:01:56you can follow us on Twitter or visit the website.
0:01:56 > 0:01:58Details on your screen.
0:02:02 > 0:02:05But first, please welcome our special guest tonight,
0:02:05 > 0:02:08probably one of the most eminent scientists alive today,
0:02:08 > 0:02:10former president of the Royal Society
0:02:10 > 0:02:12and the Astronomer Royal, Professor Martin Rees.
0:02:12 > 0:02:15APPLAUSE AND CHEERING
0:02:19 > 0:02:22- Hello, sir. How are you?- Fine.
0:02:22 > 0:02:24Let me quickly ask you about that title,
0:02:24 > 0:02:27cos it precedes you to a certain extent, the Astronomer Royal.
0:02:27 > 0:02:30Do you ever have to lug a telescope around to Buckingham Palace?
0:02:30 > 0:02:34No, I don't. It's a job with no duties at all.
0:02:34 > 0:02:36Wow! How did you get that gig? That's fantastic!
0:02:36 > 0:02:38It's so exiguous I can do it posthumously,
0:02:38 > 0:02:42- so I can keep going even after... - Really? Congratulations! Very good.
0:02:42 > 0:02:45Tell me about, we're talking about astronauts here.
0:02:45 > 0:02:47It is a dirty, messy job being an astronaut.
0:02:47 > 0:02:50It's a thankless job, would you say?
0:02:50 > 0:02:52Well, I think to be the first one was great
0:02:52 > 0:02:55but you know, when you're the 200th to go in the Space Station
0:02:55 > 0:02:58and the only publicity is about whether the loo works
0:02:58 > 0:03:01and things like that, it's not a great life.
0:03:01 > 0:03:04No, and by the way, did you ever have any aspirations?
0:03:04 > 0:03:07I think I'd have liked to be the first person up
0:03:07 > 0:03:09and I think when I'm a bit older,
0:03:09 > 0:03:11I'd be happy to go on a one-way trip to Mars.
0:03:11 > 0:03:14Really? We'll come back to the issue of one-way trips at some stage.
0:03:14 > 0:03:17Any further than Mars? Anything you'd particularly like to see?
0:03:17 > 0:03:19Cos you've seen stuff through Hubble, obviously,
0:03:19 > 0:03:22- you've seen enough stuff on telescopes?- Yes.
0:03:22 > 0:03:25Well, it's just the experience of looking back at the Earth.
0:03:25 > 0:03:27I think, once you get beyond the Earth,
0:03:27 > 0:03:29there's nothing as exciting as the Earth
0:03:29 > 0:03:31and you can see it through a telescope, but it's the experience,
0:03:31 > 0:03:34so there will be people who want to go on one-way tickets to Mars.
0:03:34 > 0:03:36Yes, it is a delightful paradox
0:03:36 > 0:03:38that the people who were most interested in the stars,
0:03:38 > 0:03:41the first thing they'd do if they ever got there was turn around
0:03:41 > 0:03:43and look back to Earth again.
0:03:43 > 0:03:46That was true of the first people who got to the Moon, wasn't it?
0:03:46 > 0:03:48They looked around and contrasted
0:03:48 > 0:03:52the sterile moonscape with the beautiful, blue, fragile Earth.
0:03:52 > 0:03:55And that was the iconic picture of the Earth
0:03:55 > 0:03:58that we've all had on our walls for the last 40 years.
0:03:58 > 0:04:01It does seem as if we may be a difficult moment.
0:04:01 > 0:04:03We may have hit limitations in space travel.
0:04:03 > 0:04:07It would be a tragedy to put these limits on space exploration
0:04:07 > 0:04:09as it's very much the final chapter
0:04:09 > 0:04:11in the story of mankind's defining need to explore,
0:04:11 > 0:04:14a journey that goes back to our very beginnings.
0:04:17 > 0:04:21It seems that we humans have a propensity for itchy feet,
0:04:21 > 0:04:26ever since our ancestors strolled out of Africa 100,000 years ago
0:04:26 > 0:04:28but it wasn't long before we realised that
0:04:28 > 0:04:31having effective means and methods
0:04:31 > 0:04:33are essential to proper exploration.
0:04:35 > 0:04:37Around 400 BC,
0:04:37 > 0:04:40the Greeks used a rudimentary knowledge of the stars to navigate.
0:04:40 > 0:04:42Despite fears of sea monsters,
0:04:42 > 0:04:46one even ventured to strange northern lands of beer drinkers
0:04:46 > 0:04:47that turned out to be Britain.
0:04:49 > 0:04:52Vikings appropriated wildlife to aid their exploration.
0:04:52 > 0:04:55Ravens were deployed from boats to guide them to new lands
0:04:55 > 0:04:59and the reward was the discovery of Iceland.
0:05:00 > 0:05:04Wildlife-based navigation systems were rare, however.
0:05:04 > 0:05:07Most explorers opted for stellar guidance.
0:05:07 > 0:05:09Mediaeval Arabs refined navigation
0:05:09 > 0:05:11with accurate star maps
0:05:11 > 0:05:13and tools to chart their position
0:05:13 > 0:05:16and the Chinese invented a portable magnetic compass.
0:05:19 > 0:05:22But navigation still had a way to go.
0:05:22 > 0:05:26In 1492, Columbus sailed the ocean blue
0:05:26 > 0:05:29and discovered what he thought was the East Indies -
0:05:29 > 0:05:33hence his insistence on calling the people who lived there Indians.
0:05:33 > 0:05:36It took quite some time for anyone to realise
0:05:36 > 0:05:39that they were, in fact, Americans.
0:05:39 > 0:05:41Columbus's Indian faux pas
0:05:41 > 0:05:43was largely because he had no idea
0:05:43 > 0:05:45how far east or west he was.
0:05:45 > 0:05:48Calculating that meant knowing the time,
0:05:48 > 0:05:51which was impossible to do without reliable seagoing clocks
0:05:51 > 0:05:54and they didn't arrive until the late 1700s.
0:05:58 > 0:06:00With location finally sorted out,
0:06:00 > 0:06:03others were adding another dimension to exploration.
0:06:03 > 0:06:05In 1783, two French brothers
0:06:05 > 0:06:09demonstrated their flying sheep experiment near Paris.
0:06:09 > 0:06:11They believed that ovine aviation
0:06:11 > 0:06:15was achieved by a special property of smoke they called levity.
0:06:17 > 0:06:21It was soon decided that the fun shouldn't be restricted to ruminants
0:06:21 > 0:06:24and man took to the air for the first time
0:06:24 > 0:06:26but unfortunately, man had no control
0:06:26 > 0:06:28over where the balloon was taking him.
0:06:30 > 0:06:35American Samuel Langley realised that useful air travel meant power.
0:06:35 > 0:06:38He had some success with rubber bands and steam
0:06:38 > 0:06:40but more often than not, ended up
0:06:40 > 0:06:41on the ground or in the river.
0:06:43 > 0:06:46By the time powered flight was reliably in the bag,
0:06:46 > 0:06:48most of the world had been explored.
0:06:48 > 0:06:50Time for a new challenge
0:06:50 > 0:06:52and a new destination.
0:06:52 > 0:06:56In the 1920s, space pioneer Robert Goddard
0:06:56 > 0:06:58invented liquid-fuelled rockets.
0:06:58 > 0:07:01He even claimed a rocket could reach the Moon,
0:07:01 > 0:07:03but not everyone was convinced.
0:07:03 > 0:07:08The New York Times smugly pointed out that nothing can fly in a vacuum
0:07:08 > 0:07:13and even though a series of cosmic dogs, astro monkeys and spacemen
0:07:13 > 0:07:18suggested otherwise, it wasn't until the day after Apollo 11 launched
0:07:18 > 0:07:20that the paper finally conceded
0:07:20 > 0:07:23that a rocket can fly in a vacuum after all,
0:07:23 > 0:07:25stating, "The Times regrets the error."
0:07:27 > 0:07:31Even landing on the Moon hasn't satisfied our wanderlust.
0:07:31 > 0:07:33We're roving on Mars,
0:07:33 > 0:07:34probing Saturn
0:07:34 > 0:07:37and voyaging beyond our solar system
0:07:37 > 0:07:40but the irony is, WE are not actually doing the exploring.
0:07:40 > 0:07:43We're now reliant on robots to be curious on our behalf.
0:07:52 > 0:07:55Am I just too much in thrall to the romance of the Apollo missions
0:07:55 > 0:07:58or is that like a sad anti-climax?
0:07:58 > 0:07:59Well, I think it's inevitable
0:07:59 > 0:08:03because as robots get better, the case for sending people gets weaker,
0:08:03 > 0:08:06and I would say, speaking as a scientist and practical man,
0:08:06 > 0:08:09there's no case whatever for sending people at all
0:08:09 > 0:08:11but as a human being, as it were,
0:08:11 > 0:08:13I'd like to feel that some people will walk on Mars
0:08:13 > 0:08:17and go beyond, so it's an adventure, no practical purpose.
0:08:17 > 0:08:18Do we learn more
0:08:18 > 0:08:22because we've put, you know, we've put Hubble up,
0:08:22 > 0:08:26we use it just as a laboratory that's remotely controlled?
0:08:26 > 0:08:30Well, it's true, if we had a real geologist walking on Mars,
0:08:30 > 0:08:33then probably, he or she would detect things
0:08:33 > 0:08:35that the Curiosity probe won't detect
0:08:35 > 0:08:39but if you add the huge extra cost of the person going there,
0:08:39 > 0:08:43it's not justified, and robots are getting better all the time,
0:08:43 > 0:08:45so I think there's no practical case for sending people.
0:08:45 > 0:08:48No practical case, but obviously, it tugs at the heartstrings.
0:08:48 > 0:08:50Sure, they'll go as explorers,
0:08:50 > 0:08:54rather like crazy people go ballooning and things like that.
0:08:54 > 0:08:55LAUGHTER
0:08:55 > 0:08:57We do have a noble history, though,
0:08:57 > 0:09:00we have, to a certain extent, conquered that environment.
0:09:00 > 0:09:03We have walked on another planet.
0:09:03 > 0:09:06I think it is wonderful that people have done
0:09:06 > 0:09:07but we shouldn't kid ourselves
0:09:07 > 0:09:10that there's anywhere as clement to live in
0:09:10 > 0:09:13as the Antarctic or the top of Everest, so we're kidding ourselves
0:09:13 > 0:09:15if we think it will be an escape from the Earth's problems.
0:09:15 > 0:09:18Now, the issue of environment is vital to this, of course.
0:09:18 > 0:09:21We have evolved to survive in this environment, rather than in space,
0:09:21 > 0:09:24so when we go into space, we have to bring our environment with us,
0:09:24 > 0:09:28whether in a capsule, or even more iconically, in the spacesuit.
0:09:28 > 0:09:29But if you've ever wondered
0:09:29 > 0:09:32what exactly, other than the astronaut, is inside the suit,
0:09:32 > 0:09:33Mark has gone to find out.
0:09:33 > 0:09:36'Ignition sequence starts.
0:09:36 > 0:09:42'Five, four, three, two, one...'
0:09:42 > 0:09:45Good evening. When astronauts leave the safe confines
0:09:45 > 0:09:48of the International Space Station, they wear one of these.
0:09:48 > 0:09:51It's called an Extravehicular Mobility Unit
0:09:51 > 0:09:54but you know it and I know it as a spacesuit.
0:10:00 > 0:10:04Since Neil Armstrong and Buzz Aldrin stepped out on the Moon in 1969,
0:10:04 > 0:10:06the spacesuit has evolved
0:10:06 > 0:10:09and I'm going to show you some of those changes
0:10:09 > 0:10:11by taking off this suit bit by bit.
0:10:13 > 0:10:14Spacesuits have all the systems
0:10:14 > 0:10:18needed to protect astronauts from extreme temperatures,
0:10:18 > 0:10:20micro-meteoroids and the void of outer space
0:10:20 > 0:10:23but first and foremost, they need to breathe.
0:10:27 > 0:10:30The air is supplied by the primary life-support system.
0:10:30 > 0:10:33Back in the Apollo missions, that was a removable backpack
0:10:33 > 0:10:37but here, it's fully integrated in the top half of the suit.
0:10:37 > 0:10:39That makes it incredibly heavy.
0:10:39 > 0:10:41That's why I'm attached to this hoist.
0:10:43 > 0:10:46The air isn't just for breathing. It also inflates the suit.
0:10:47 > 0:10:50This pressurisation provides protection
0:10:50 > 0:10:52from the near-perfect vacuum.
0:10:52 > 0:10:55'Roger, zero G and I feel fine.'
0:10:55 > 0:10:57It stops bodily fluids from boiling
0:10:57 > 0:11:02and turns a piece of clothing into a one-person spacecraft.
0:11:02 > 0:11:06Now to get the suit off. First, the helmet.
0:11:06 > 0:11:10I think I'm going to need a bit of help, though.
0:11:10 > 0:11:15'The helmet fits onto the suit with a vitally important vacuum-proof seal.'
0:11:18 > 0:11:19Thank you.
0:11:19 > 0:11:22It comes with a distinctive gold-coated visor
0:11:22 > 0:11:25to shield the eyes from unfiltered sunlight
0:11:25 > 0:11:27but this has the downside
0:11:27 > 0:11:31of making it hard to identify astronauts in photos.
0:11:31 > 0:11:33Underneath the helmet is the communication cap
0:11:33 > 0:11:35which contains the microphones and earpieces
0:11:35 > 0:11:38that allow the astronaut to communicate with Mission Control.
0:11:38 > 0:11:41It's often referred to as the Snoopy cap,
0:11:41 > 0:11:43after the cartoon dog that looks similar,
0:11:43 > 0:11:45and fond as I am of it, it's coming off now.
0:11:45 > 0:11:49'Five, four, three...'
0:11:49 > 0:11:51Thanks.
0:11:51 > 0:11:53'..two, one...'
0:11:53 > 0:11:57'Contact, 100%. Modulation is go.'
0:11:57 > 0:12:02Most of the protection comes from the suit's hard upper torso and trousers.
0:12:02 > 0:12:05In the 1960s, when very few people went into space,
0:12:05 > 0:12:09astronauts were lucky enough to benefit from bespoke tailoring,
0:12:09 > 0:12:11all-in-one suits made to measure.
0:12:11 > 0:12:13But with the advent of the International Space Station
0:12:13 > 0:12:16and the Space Shuttle, people had to share,
0:12:16 > 0:12:18and spacesuits became modular,
0:12:18 > 0:12:21allowing different-sized hands and legs to be screwed on.
0:12:24 > 0:12:28There is one part of the suit that's still custom built - the gloves.
0:12:28 > 0:12:32A mould of the astronaut's hands is taken to ensure a tight fit
0:12:32 > 0:12:34and there's one additional component.
0:12:36 > 0:12:38The fingertips feature battery-powered heaters
0:12:38 > 0:12:41to stop the extremities from getting chilly -
0:12:41 > 0:12:44something the Apollo astronauts had to do without.
0:12:44 > 0:12:47Without the protective atmosphere of a planet,
0:12:47 > 0:12:51astronauts needed to be shielded from the extreme cold and extreme heat.
0:12:51 > 0:12:55And the suit does that with 12 layers of material,
0:12:55 > 0:12:59but it's the silvery ones that do most of the work.
0:12:59 > 0:13:01There's five aluminium-coated layers.
0:13:01 > 0:13:05Now, these protect against solar and cosmic radiation.
0:13:05 > 0:13:08This was the outer shell on the Mercury missions,
0:13:08 > 0:13:11when the astronauts never left the spaceship,
0:13:11 > 0:13:14but when they first ventured out in Gemini and Apollo,
0:13:14 > 0:13:18there was the additional threat from high-speed micro-meteoroids,
0:13:18 > 0:13:20meaning that one more layer was required.
0:13:20 > 0:13:23Above all these layers is the iconic white shell.
0:13:23 > 0:13:25It's made of Kevlar, Teflon and Gore-Tex
0:13:25 > 0:13:29and it's extremely tough and fireproof.
0:13:29 > 0:13:32Now you'll see why it takes so much training to be an astronaut -
0:13:32 > 0:13:34just to get this thing off!
0:13:42 > 0:13:46'All this insulation comes with the unexpected risk of overheating.
0:13:46 > 0:13:49'Early astronauts came back drenched in sweat
0:13:49 > 0:13:52'and condensation caused the visors to fog up,
0:13:52 > 0:13:56'so it quickly became clear that a high-tech undergarment was required.'
0:13:59 > 0:14:02I know, but it's comfier than it looks.
0:14:02 > 0:14:04It's called a liquid cooling garment
0:14:04 > 0:14:06and it was originally developed by the RAF
0:14:06 > 0:14:10and then NASA took it and developed it for the Apollo space missions,
0:14:10 > 0:14:13and what it does is channel water down little tubes around the body,
0:14:13 > 0:14:15wicking the heat away.
0:14:16 > 0:14:20'Beneath this, there was one final problem that had to be dealt with.'
0:14:21 > 0:14:25Apollo astronauts had tubes and bags to remove waste.
0:14:26 > 0:14:31But luckily, the International Space Station now has toilets.
0:14:41 > 0:14:43You were proud, weren't you, putting it on?
0:14:43 > 0:14:46- Is it really heavy? - It's very, very heavy indeed.
0:14:46 > 0:14:49If I hadn't been held up by a winch, I would have collapsed on the floor.
0:14:49 > 0:14:53I mean, it's specifically designed to fight meteorites
0:14:53 > 0:14:56and lack of air and the temperature and everything.
0:14:56 > 0:14:58There are various myths about this.
0:14:58 > 0:15:00If you floated off into space, if you got hit on the mask,
0:15:00 > 0:15:03you'd instantly freeze.
0:15:03 > 0:15:05You'd get very cold quite quickly,
0:15:05 > 0:15:08but you wouldn't instantly freeze because there's no convection.
0:15:08 > 0:15:12It's not like you swim in water and it draws the heat off your body.
0:15:12 > 0:15:17Your blood is going to start to boil because of the reduced pressure and
0:15:17 > 0:15:22then you are obviously going to asphyxiate quite quickly.
0:15:22 > 0:15:25People think they might hold their breath
0:15:25 > 0:15:26but then your lungs just explode.
0:15:26 > 0:15:30Which is a bad thing, so you have to breathe out while thinking,
0:15:30 > 0:15:33"This will be my last breath unless someone captures me,"
0:15:33 > 0:15:34in Douglas Adams style.
0:15:34 > 0:15:37The temperature at which things boil dramatically decreases.
0:15:37 > 0:15:40What happens is that your vapour pressure...the temperature
0:15:40 > 0:15:45of the vapour pressure goes down, so things start quickly boiling.
0:15:45 > 0:15:48The latent heat of that freezes you, so you get very cold,
0:15:48 > 0:15:49very quickly.
0:15:49 > 0:15:52- But you're dead at that stage anyway.- You're dead at that stage.
0:15:52 > 0:15:54- You've boiled yourself to death. Can we see?- Let's have a go.
0:15:54 > 0:15:58If we get some water we'll try and make some fake blood.
0:15:58 > 0:16:01Can I just borrow that little bit of water there if you don't mind.
0:16:01 > 0:16:04Thank you very much. Just a little bit.
0:16:06 > 0:16:11I am going to put a little bit of food colouring in this
0:16:11 > 0:16:14and this will change the boiling temperature of it slightly.
0:16:14 > 0:16:19- Yeah. Especially that much!- I don't use food colouring very often.
0:16:19 > 0:16:24OK, well, I have very thick blood, all right? Would that pass?
0:16:24 > 0:16:31- Are you happy with that?- Fine. That's some blood in your veins.
0:16:31 > 0:16:33So now, you are fine, you are in your spacesuit, but,
0:16:33 > 0:16:38suddenly your spacesuit fails, you exposed to the vacuum of space!
0:16:38 > 0:16:41Which we'll now recreate. This is quite dramatic.
0:16:41 > 0:16:43Don't look away, because it happens relatively quickly.
0:16:43 > 0:16:46This is pumping air out of the bottom here, it's coming out there.
0:16:46 > 0:16:50That cloud is the vapour condensing into a cloud,
0:16:50 > 0:16:52it's been sucked out too.
0:16:52 > 0:16:56- You see the pressure here.- The pressure is dropping very quickly.
0:16:56 > 0:17:00And you can see a froth, so now it's starting to froth and oh, yes,
0:17:00 > 0:17:03that's probably the moment at which you aren't feeling very well.
0:17:03 > 0:17:05LAUGHTER
0:17:05 > 0:17:08Because presumably your eyes have done this as well,
0:17:08 > 0:17:10all the fluid in your body, the brain?
0:17:10 > 0:17:13The fluids are doing this, yes, that's the big problem.
0:17:13 > 0:17:15I think it's worth seeing that again.
0:17:15 > 0:17:19This is the blood boiling moment once again. Wow! That's dramatic.
0:17:19 > 0:17:22We are essentially saying that bit at the end of Total Recall,
0:17:22 > 0:17:26where he's thrashing around the planet of Mars and his eyes expand.
0:17:26 > 0:17:28That's scientifically accurate.
0:17:28 > 0:17:31You'd expand. You would expand, actually.
0:17:31 > 0:17:34People who experienced very low vacuums show their hands
0:17:34 > 0:17:36and limbs do get very much bigger.
0:17:36 > 0:17:38Can I just stop this
0:17:38 > 0:17:41and take this out for the sake of calming down that noise?
0:17:41 > 0:17:44Lovely. Good stuff. I want to show you something else.
0:17:44 > 0:17:46This is genuinely astonishing.
0:17:46 > 0:17:49Space travel is just one long engineering challenge after
0:17:49 > 0:17:51another and one thing that fascinates me is
0:17:51 > 0:17:54the possibility of humans travelling out beyond the solar system,
0:17:54 > 0:17:56maybe to populate another planet in another solar system.
0:17:56 > 0:17:59I'm not the only person who has imagined this.
0:17:59 > 0:18:02We've this giant blow-up here of one of the most astonishing
0:18:02 > 0:18:03documents I have ever seen.
0:18:03 > 0:18:07It's the Rockwell Integrated Space Plan written by a man called
0:18:07 > 0:18:11Ronald Jones and is basically a step-by-step flowchart of what
0:18:11 > 0:18:15we'd need to invent in order to get to a point...I mean,
0:18:15 > 0:18:18it's difficult...we start here in the '80s,
0:18:18 > 0:18:20really where we were,
0:18:20 > 0:18:23first-generation reusable spacecraft.
0:18:23 > 0:18:27The American space shuttle Challenger, Columbia, Discovery.
0:18:27 > 0:18:32Down here...that's 1883...down here to 2100 which is human
0:18:32 > 0:18:35expansion into the cosmos begins.
0:18:35 > 0:18:37LAUGHTER
0:18:37 > 0:18:39It's full of cool phrases like that the entire way through.
0:18:39 > 0:18:41The only thing obviously it's slightly optimistic.
0:18:41 > 0:18:45This made sense - the US International Space Station Project,
0:18:45 > 0:18:48but that's happened a couple of times now, back in the mid '90s.
0:18:48 > 0:18:51By the time we get to where we are here 2008-2012 we see
0:18:51 > 0:18:54the International Lunar Base has expanded,
0:18:54 > 0:18:57the outpost is there and the Moon Port,
0:18:57 > 0:19:00that seems a little bit further afield than 2014.
0:19:00 > 0:19:03- Have you been examining this? - There's some weird stuff.
0:19:03 > 0:19:06- They start a shop here. I don't know why they need to shop.- A shop!
0:19:06 > 0:19:09There's obviously going to be a shop to sell Mars bars
0:19:09 > 0:19:13and merchandise and T-shirts of I Live On The Moon Post.
0:19:13 > 0:19:16How do you think we're going to fund the rest of this if the DVD sales
0:19:16 > 0:19:19don't work out?
0:19:19 > 0:19:23Unlimited safe solar energy for Earth? Create new
0:19:23 > 0:19:27moons for Mars, if required.
0:19:27 > 0:19:30- They'll always be required. - Who doesn't need more new moons?
0:19:30 > 0:19:34This is the kind of ambition we've lost, you know.
0:19:34 > 0:19:36The only thing really missing from here is a space elevator,
0:19:36 > 0:19:39if you ask me, because I think actually that's a far better
0:19:39 > 0:19:42way to spend this kind of ambition but you know,
0:19:42 > 0:19:45we just need a bit more of this and I think it should be made
0:19:45 > 0:19:49into wallpaper and papered on every child's bedroom across the globe.
0:19:49 > 0:19:54Yeah! Forget princess wallpaper and things like that.
0:19:54 > 0:19:56One day we'll go, "Put this up", and depress them.
0:19:56 > 0:19:59This massive flowchart.
0:19:59 > 0:20:01Yes, maybe we stalled there
0:20:01 > 0:20:04but there are still people who are hoping to make this a reality.
0:20:04 > 0:20:06My friend Josh Widdicombe has been off to Houston, Texas,
0:20:06 > 0:20:08the home of NASA, to investigate.
0:20:13 > 0:20:17When I was growing up I thought space travel was really exciting.
0:20:17 > 0:20:21We'd been to the moon, what next? Are we going to Mars?
0:20:21 > 0:20:25Are we going beyond Mars? Are we all going to end up living in space?
0:20:25 > 0:20:29This hasn't happened, has it? And I want to know why not.
0:20:29 > 0:20:32I want to know what's the future for human space travel.
0:20:32 > 0:20:36So I've come to its spiritual home - Houston, Texas, to talk to
0:20:36 > 0:20:39the people who are busy trying to get humans into space.
0:20:42 > 0:20:45Physicist Paul Davies, has published a manifesto for a manned mission
0:20:45 > 0:20:47to Mars.
0:20:47 > 0:20:50If I am honest with you, it's a little out there.
0:20:50 > 0:20:54I think the only way we're going to be able to afford to go to
0:20:54 > 0:20:56Mars is a one-way mission.
0:20:56 > 0:20:58I think if Mars is such a great place to go,
0:20:58 > 0:21:01leave the astronauts there. They can do some fantastic work, they can...
0:21:01 > 0:21:04If they're scientists they can do some good science.
0:21:04 > 0:21:08- You're looking sceptical. - I'm not signing up.
0:21:08 > 0:21:11This isn't a suicide mission, I should explain.
0:21:11 > 0:21:14You're not saying to four people, "Right, you've got enough
0:21:14 > 0:21:17"oxygen for three weeks. After that, tough."
0:21:17 > 0:21:20What you are saying is you are going to be establishing
0:21:20 > 0:21:24base camp for a new permanent human presence on the Red Planet.
0:21:24 > 0:21:27We'll send the sandwiches and the letters from home and the equivalent
0:21:27 > 0:21:31and eventually other colonists will arrive and join you.
0:21:31 > 0:21:35- Would you do it yourself?- I'd love to go, but my wife won't let me.
0:21:35 > 0:21:37How very convenient!
0:21:37 > 0:21:41I must admit I don't get why Mars has to be a one-way mission.
0:21:41 > 0:21:44So I'm going to meet a rocket expert, Eric Davis, to see
0:21:44 > 0:21:46if we can't just make it a round trip.
0:21:46 > 0:21:48- Hello.- How are you doing?
0:21:48 > 0:21:52'At the moment, we go into space using chemically propelled rockets.
0:21:52 > 0:21:56'Eric says they're going to be no good for getting us to Mars.
0:21:56 > 0:21:58'Apparently, it all comes down to something called
0:21:58 > 0:21:59'the rocket equation.'
0:21:59 > 0:22:03Basically, the change in velocity is equal to the exhaust velocity
0:22:03 > 0:22:07- times the natural log of...- 'I'm not going to lie, I'm lost already.
0:22:07 > 0:22:11'Luckily, Eric has got an easier way to explain it.'
0:22:15 > 0:22:18- Eric, I'm ready. - Here's your rocket propulsion.
0:22:18 > 0:22:24'OK, it's not the perfect analogy, but imagine I'm a spacecraft
0:22:24 > 0:22:27'and this fire extinguisher is my fuel tank.'
0:22:27 > 0:22:30Five, four, three,
0:22:30 > 0:22:33two, one...
0:22:33 > 0:22:37MUSIC: "2001 - A Space Odyssey" by Alex North
0:22:41 > 0:22:44Houston, we have a problem.
0:22:44 > 0:22:47'What Eric's trying to tell me is that to get to Mars with chemical
0:22:47 > 0:22:50'propulsion, so much of your spacecraft would have to be fuel,
0:22:50 > 0:22:55'a whopping 95% - that to build a rocket with enough fuel to get
0:22:55 > 0:22:58'there and back would be completely impractical.'
0:23:02 > 0:23:04So how does it exactly work?
0:23:04 > 0:23:09A nuclear thermal rocket is basically atomic fission.
0:23:09 > 0:23:12It's the fissioning of uranium atoms in a hot core.
0:23:12 > 0:23:16The core heats up from the nuclear radiation
0:23:16 > 0:23:18and you are going to pass liquid fuel through.
0:23:18 > 0:23:22It gets heated up and gets expelled out the rocket engine.
0:23:22 > 0:23:24The rocket goes very fast.
0:23:24 > 0:23:27When do you think we're going to be launching this mission to Mars?
0:23:27 > 0:23:30We could do nuclear rocket engines at any time.
0:23:30 > 0:23:33It's just a matter of whether there's the political will
0:23:33 > 0:23:36and the money devoted to making it happen.
0:23:36 > 0:23:40'So it sounds like we've got the technology almost sorted.
0:23:40 > 0:23:41'But what about us?
0:23:41 > 0:23:44'How do we know that humans could actually survive
0:23:44 > 0:23:47'these long space missions?
0:23:47 > 0:23:51'Here in Galveston, Texas, NASA are trying to find out by paying
0:23:51 > 0:23:53'people to stay in bed.'
0:23:53 > 0:23:57Apparently, lying horizontal for weeks at a time mimics
0:23:57 > 0:24:01the effect of zero gravity on the body, allowing scientists to
0:24:01 > 0:24:05monitor one of the biggest problems with hanging out in space -
0:24:05 > 0:24:07the gradual weakening of bone and muscle.
0:24:07 > 0:24:13Dirk has been at it for two weeks. Luckily, he's only got 57 days to go.
0:24:13 > 0:24:18- Hello.- Hey.- How is it going? I'm Josh.- I'm Dirk.- Nice to meet you.
0:24:18 > 0:24:22- You can't get up, obviously. - No, no. I am stuck here.
0:24:22 > 0:24:26Let's cut to the big question. How do you go to the bathroom?
0:24:26 > 0:24:28That's the hardest thing to get used to.
0:24:28 > 0:24:30You have to do everything from the bed
0:24:30 > 0:24:35and they collect all of your urine and, of course, use a bedpan.
0:24:35 > 0:24:37So that's the hardest part of this, I think.
0:24:37 > 0:24:40To combat the problem of withering muscle and bone
0:24:40 > 0:24:41they've created this monster.
0:24:41 > 0:24:44OK. What's happening here?
0:24:44 > 0:24:46'This is a vertical treadmill' -
0:24:46 > 0:24:49'the Earth equivalent of what astronauts
0:24:49 > 0:24:51'use to stay healthy in space.'
0:24:51 > 0:24:53I don't like this at all.
0:24:53 > 0:24:56'Basically, this kind of exercise keeps astronauts' bones healthy
0:24:56 > 0:25:01'on long missions by providing enough resistance for a proper workout.'
0:25:01 > 0:25:02Tell my family I love them.
0:25:03 > 0:25:05Let's do this.
0:25:05 > 0:25:07All right, Josh, here we go.
0:25:07 > 0:25:10You're going to start at two miles an hour in three, two, one.
0:25:10 > 0:25:14- I like the way...oh, my God, that's fast. Is that two miles an hour?- Yes.
0:25:14 > 0:25:18It feels like I am really making progress towards the ceiling.
0:25:18 > 0:25:20- It's all right. You want to go a little faster?- Why not?
0:25:20 > 0:25:23- I'm only going to get to do this once.- Here we go,
0:25:23 > 0:25:24three miles an hour.
0:25:24 > 0:25:29That is...it's a real jog. I reckon I can do four.
0:25:29 > 0:25:32All right, let's give four a shot. Here we go.
0:25:32 > 0:25:36- Three, two, one, four miles an hour. - Yeah, I can't do four.
0:25:39 > 0:25:42In deep space, you'd have to do two hours of exercise a day.
0:25:42 > 0:25:47I can barely last ten minutes on this, which makes me wonder what
0:25:47 > 0:25:51kind of person actually has what it takes to do this for real?
0:25:51 > 0:25:54I think it's finally time to meet an astronaut!
0:25:57 > 0:26:00'Andy Thomas has been in space four times.'
0:26:00 > 0:26:01Pleasure to meet you.
0:26:02 > 0:26:08'He's spent 130 days on the Mir Space Station and he was on the first
0:26:08 > 0:26:13'flight back into space after the Columbia disaster in 2003.
0:26:13 > 0:26:14'I asked him
0:26:14 > 0:26:17'whether he thinks we should be really trying to get to Mars?'
0:26:17 > 0:26:21Can you imagine anything more mind blowing than walking on Mars?
0:26:21 > 0:26:23- No.- Everything is a different planet,
0:26:23 > 0:26:27the physics is different and nature behaves differently
0:26:27 > 0:26:30and you are on this ancient, windswept surface.
0:26:30 > 0:26:33I think that would be just a wonderful experience.
0:26:33 > 0:26:37If we get to Mars, can you imagine that we'll be living there?
0:26:37 > 0:26:39There'll be people born on Mars.
0:26:39 > 0:26:43I think ultimately you'll get to that point. That's colonisation.
0:26:43 > 0:26:47That will happen but it's a long way off, probably 100 years away.
0:26:47 > 0:26:50One day we'll have some kind of technical breakthrough that
0:26:50 > 0:26:52will develop an improved propulsion system
0:26:52 > 0:26:54and that will open up the solar system.
0:26:54 > 0:26:56Do you think that's a serious proposition?
0:26:56 > 0:27:00Yes, eventually, it's not a question of if, but when, I'm sure.
0:27:02 > 0:27:04There you go. You heard it from an astronaut.
0:27:04 > 0:27:08In just 100 years' time, my great-grandchildren
0:27:08 > 0:27:11and your great-grandchildren could well be Martians.
0:27:13 > 0:27:14Please welcome to this sofa Josh Widdicombe
0:27:14 > 0:27:17and another special guest, Dr Iya Whiteley,
0:27:17 > 0:27:20the Deputy Director of the Centre For Space Medicine at UCL.
0:27:28 > 0:27:31There's a number of questions from that. Congratulations.
0:27:31 > 0:27:34You look like some weird meat puppet being extended from the ceiling.
0:27:34 > 0:27:36The astronaut got excited talking about the different
0:27:36 > 0:27:39physics on Mars. There isn't a different physics on Mars
0:27:39 > 0:27:43- per se, is there?- Different geology, but not physics.- OK, grand.
0:27:43 > 0:27:46It's not suddenly "up is down and down is up" when you get to Mars.
0:27:46 > 0:27:49It's just red, more red. Were you disheartened?
0:27:49 > 0:27:54No, I came home inspired. Not to go to Mars.
0:27:54 > 0:27:58You could see what I would achieve there, but no,
0:27:58 > 0:28:02I went there thinking it was a kind of non-starter, not going to happen.
0:28:02 > 0:28:05Certainly talking to Andy the astronaut, you suddenly go,
0:28:05 > 0:28:07these are people that are in the industry that say
0:28:07 > 0:28:09this is going to happen.
0:28:09 > 0:28:14It's almost less the technological problems than the political ones.
0:28:14 > 0:28:16Not backing it financially.
0:28:16 > 0:28:19It's an enormous project financially, in terms
0:28:19 > 0:28:24of resources, that amount of fuel and everything to draw together.
0:28:24 > 0:28:28The Apollo programme was done to beat the Russians, not for science
0:28:28 > 0:28:32and the question is, will anyone do it for that motive?
0:28:32 > 0:28:36I would guess the Chinese might, they might feel they want to leapfrog what
0:28:36 > 0:28:41the Americans did and send people to Mars and they could do if they tried.
0:28:41 > 0:28:43Apart from that, I don't really see anyone's got the motive to
0:28:43 > 0:28:46spend the money until it becomes much cheaper.
0:28:46 > 0:28:49Until then, we're discussing possibly going, but not coming back.
0:28:49 > 0:28:51This changes everything to a certain extent.
0:28:51 > 0:28:55Iya, you deal with the medical side of this.
0:28:55 > 0:28:57For someone to take a journey of that length of time
0:28:57 > 0:29:01away from Earth, psychologically, what would the effects of that be?
0:29:01 > 0:29:06One factor is actually being bored really, because it's a long journey.
0:29:06 > 0:29:10So when we're actually coming back, the issue is that you've achieved
0:29:10 > 0:29:14the greatest thing in your career, your dreams and probably the
0:29:14 > 0:29:16first person to step on Mars
0:29:16 > 0:29:18and now you have to travel over a year back.
0:29:18 > 0:29:22Really, these people have to be quite motivated
0:29:22 > 0:29:25when they come back on Earth.
0:29:25 > 0:29:27Maybe a year and a half of comedown
0:29:27 > 0:29:29from the euphoria of having reached Mars?
0:29:29 > 0:29:32Also having to spend that amount of time with what
0:29:32 > 0:29:35are essentially work colleagues must be the most annoying thing.
0:29:35 > 0:29:38It's always going to be confined spaces - a tight,
0:29:38 > 0:29:40enclosed environment.
0:29:40 > 0:29:41One of the things of the shock
0:29:41 > 0:29:45when people come up to international space stations is the air.
0:29:45 > 0:29:49It has all the bodily human smells that you wouldn't want to
0:29:49 > 0:29:52come across in a gym changing room.
0:29:52 > 0:29:55When they get the resupply ship, and, for example,
0:29:55 > 0:29:57it comes with goods, and they will open it
0:29:57 > 0:30:00and people just gather around
0:30:00 > 0:30:03because they get this woof of air of fresh food.
0:30:03 > 0:30:08I know a story from the Russian cosmonauts that they when they packed
0:30:08 > 0:30:12they packed in pickled, well, salted cucumbers,
0:30:12 > 0:30:14and they put them in the suit.
0:30:14 > 0:30:18So when they got to the space station and they opened the suit,
0:30:18 > 0:30:20the smell was released and they really like that smell.
0:30:20 > 0:30:22It reminds you of home.
0:30:22 > 0:30:27Cucumber? It wouldn't remind me of my home. It's not my thing.
0:30:27 > 0:30:30- Does this make you even less...? - Yeah.
0:30:30 > 0:30:35I met Andy - the astronaut that I met - his wife is an astronaut
0:30:35 > 0:30:39and you're not allowed to go into space with your spouse.
0:30:39 > 0:30:40That is not allowed.
0:30:40 > 0:30:44I think NASA's feeling about that was that if there is a disaster,
0:30:44 > 0:30:47they don't wish to orphan the family.
0:30:47 > 0:30:49- It's not that they'd bicker?- No.
0:30:49 > 0:30:54One of my favourite theories is that of Professor Samuel Lepkovsky -
0:30:54 > 0:30:56he was a professor of poultry husbandry
0:30:56 > 0:30:58in Berkeley University, California -
0:30:58 > 0:31:03who suggested that we would save weight by sending really fat people,
0:31:03 > 0:31:08because really fat people could survive on their own reserves of fat
0:31:08 > 0:31:09for up to 90 days
0:31:09 > 0:31:12and that would save you packing food.
0:31:12 > 0:31:14- This is the... - They are packing food.
0:31:14 > 0:31:19They already had begun the process of packing food some time before it.
0:31:19 > 0:31:21Still to come on the show, Mark tests a brand-new rocket fuel
0:31:21 > 0:31:24and Helen Czerski goes on the hunt to find
0:31:24 > 0:31:26an invisible cosmic killer.
0:31:26 > 0:31:30And Alok asks whether we should communicate with aliens.
0:31:30 > 0:31:34APPLAUSE
0:31:36 > 0:31:38One of the requirements
0:31:38 > 0:31:41if you are going to travel into deep space
0:31:41 > 0:31:44will be to make your own tools, make your own equipment,
0:31:44 > 0:31:49for which you need this - the much vaunted 3D printer.
0:31:49 > 0:31:52And it doesn't disappoint. This thing will make 3D objects.
0:31:52 > 0:31:55You model them in the computer, in a CAD file.
0:31:55 > 0:31:57You press "print" and out comes the object.
0:31:57 > 0:31:59And it really could be revolutionary.
0:31:59 > 0:32:01This could be the third industrial revolution.
0:32:01 > 0:32:05But in the context of space, you're out there
0:32:05 > 0:32:07and need to make all sorts of objects.
0:32:07 > 0:32:11A nozzle might break or you might need a new replacement cog.
0:32:11 > 0:32:14You programme it in - all the parts will be in CAD file with you,
0:32:14 > 0:32:16or mission control would send them to you -
0:32:16 > 0:32:17you press "print" and out it comes.
0:32:17 > 0:32:21Give me an example of something that's been built.
0:32:21 > 0:32:24This isn't the first thing you'd need to be able to build,
0:32:24 > 0:32:26but what this illustrates is that's a 3D object
0:32:26 > 0:32:29that came out of this printer - it started as a CAD file.
0:32:29 > 0:32:31The other thing is, it's giant,
0:32:31 > 0:32:34but you can change the size of things by clicking a button.
0:32:34 > 0:32:36It's all about individualisation.
0:32:36 > 0:32:40So rather than creating expensive moulds and getting the sizings...
0:32:40 > 0:32:43Are you opening a merchandising stall? Is that what you're doing?
0:32:43 > 0:32:47And in case you're wondering if you can only make very basic objects,
0:32:47 > 0:32:50you can actually make stuff with moving parts, cogs.
0:32:50 > 0:32:54- Like replacement hips? Replacement teeth?- Yep.
0:32:54 > 0:32:57All these things. So you could medically prolong your own life.
0:32:57 > 0:33:01That's another thing. In space, the future of body parts...
0:33:01 > 0:33:05People are talking about producing scaffolds to create new organs.
0:33:05 > 0:33:09It is revolutionary. It's only going to get more exciting.
0:33:09 > 0:33:13It's like in the 1980s, when personal computers were just starting up.
0:33:13 > 0:33:14It is possible that everyone will have
0:33:14 > 0:33:16one of these in their houses in the future.
0:33:16 > 0:33:19Instead of buying stuff from shops, you just buy the information
0:33:19 > 0:33:21and you press print.
0:33:21 > 0:33:24What are we making today? What's it going to create?
0:33:24 > 0:33:27It's important to have sport when you're on another planet.
0:33:27 > 0:33:28Not just useful objects.
0:33:28 > 0:33:31While you are waiting for something to break,
0:33:31 > 0:33:35we're printing a sporting object which I will tell you of later.
0:33:35 > 0:33:38If you want to see some of the miraculous medical uses
0:33:38 > 0:33:43of a 3D printer, go to our website where there's a fantastic report.
0:33:43 > 0:33:45We'll be back and see the results of this. I'm excited.
0:33:45 > 0:33:47I've wanted to see one of these for ages.
0:33:47 > 0:33:50We've been to-ing and fro-ing into near space for 50-odd years.
0:33:50 > 0:33:53Only recently, we've begun to understand the dangers
0:33:53 > 0:33:54we literally didn't see coming.
0:33:54 > 0:33:58Helen Czerski reports on a fascinating scientific mystery.
0:34:04 > 0:34:05During the Apollo missions,
0:34:05 > 0:34:09humans travelled further from Earth than ever before.
0:34:09 > 0:34:13They made history. They walked on the moon.
0:34:13 > 0:34:17Saw unprecedented views of our planet.
0:34:17 > 0:34:20But they also reported something very strange.
0:34:22 > 0:34:26They saw mysterious white flashes when their eyes were closed.
0:34:26 > 0:34:30Mission control was so concerned they asked the astronauts
0:34:30 > 0:34:31to record every flash.
0:34:32 > 0:34:35They weren't sure but they had a hunch that they were caused by
0:34:35 > 0:34:40a kind of radiation originating from outer space called cosmic rays.
0:34:42 > 0:34:46Cosmic rays are charged particles travelling extremely quickly
0:34:46 > 0:34:48through interstellar space.
0:34:48 > 0:34:50They can be really damaging to living tissue.
0:34:50 > 0:34:52But down here on Earth we're protected
0:34:52 > 0:34:56because the Earth's magnetic field acts as a shield.
0:34:56 > 0:35:00For the Apollo 16 mission, NASA developed a special device
0:35:00 > 0:35:04to find out if cosmic rays were causing the flashes.
0:35:04 > 0:35:08A helmet that could detect the energy levels of single particles.
0:35:09 > 0:35:14The astronauts ran several tests with it and the results were conclusive -
0:35:14 > 0:35:17cosmic rays from deep space were indeed penetrating
0:35:17 > 0:35:20the astronauts' eyes and interfering with the cells
0:35:20 > 0:35:21on the back of the retina.
0:35:21 > 0:35:23And that led to a question.
0:35:24 > 0:35:28If a single particle could produce an effect you could see,
0:35:28 > 0:35:31what else were these particles doing to the tissues of the body?
0:35:31 > 0:35:34The biggest fear was that the high levels of cosmic radiation
0:35:34 > 0:35:37that exist in deep space would lead to cancer.
0:35:39 > 0:35:41'So to understand the risks,
0:35:41 > 0:35:44'NASA established a space radiation laboratory
0:35:44 > 0:35:47'here at Brookhaven National Laboratory in Long Island.
0:35:49 > 0:35:52'Frank Cucinotta, who heads up NASA's programme here,
0:35:52 > 0:35:54'has come to show me around.'
0:35:54 > 0:35:57OK, so this is the computer control system.
0:35:57 > 0:36:00'Highly charged particles are so dangerous
0:36:00 > 0:36:03'I'm not allowed inside the radiation chamber.
0:36:03 > 0:36:06'But what they do here is fire a beam of particles
0:36:06 > 0:36:10'at human and animal tissues, like lung, stomach and brain -
0:36:10 > 0:36:13'the soft tissues most vulnerable to cancers -
0:36:13 > 0:36:17'to find out what kind of damage cosmic rays cause.
0:36:18 > 0:36:22'And whether there's such a thing as a safe dose for humans.'
0:36:22 > 0:36:25- MESSAGE:- Attention. Attention. Beam is evident.
0:36:27 > 0:36:30'What they're finding is that cosmic ray damage is different to
0:36:30 > 0:36:34'any other form of radiation we've ever come across.'
0:36:34 > 0:36:39We're looking at images of brain cells where the blue colour
0:36:39 > 0:36:43indicates the nucleus of the brain cell and the green colour shows you
0:36:43 > 0:36:47a wake of DNA damage that's been caused by the ion particle.
0:36:47 > 0:36:50What's striking is that a single cosmic ray has come right the way
0:36:50 > 0:36:55through these two nuclei and caused a really strong trail of damage.
0:36:55 > 0:36:57But if it had been an X-ray, it might just have caused
0:36:57 > 0:37:00one spot on one of these nuclei.
0:37:00 > 0:37:04So as far as radiation goes, a cosmic ray has much more bang for its buck.
0:37:04 > 0:37:08Yeah, it's much more of a concern. It's a qualitative difference.
0:37:08 > 0:37:10'The reason cosmic rays are so damaging,
0:37:10 > 0:37:12'is because they're thought to originate
0:37:12 > 0:37:15'in some of the most energetic events in the universe -
0:37:15 > 0:37:16'supernova explosions.
0:37:16 > 0:37:19'Where charged particles are accelerating close to
0:37:19 > 0:37:22'the speed of light and spat out into the cosmos.
0:37:23 > 0:37:26'Frank's team has shown that just one of these particles
0:37:26 > 0:37:29'has the power to charge through human tissue,
0:37:29 > 0:37:33'strip molecules of electrons and physically break the DNA -
0:37:33 > 0:37:37'potentially leading to cell mutations and cancer.
0:37:37 > 0:37:41'So far, we've seen astronauts with the highest levels of exposure
0:37:41 > 0:37:45'develop early cataracts because the soft tissue of the eye
0:37:45 > 0:37:47'is most vulnerable to damage.
0:37:47 > 0:37:49'The current thinking is that on a mission to Mars,
0:37:49 > 0:37:54'the change of developing terminal cancer could be as high as 30%.
0:37:55 > 0:37:57'I asked Frank what the solutions are.'
0:37:57 > 0:37:59We have some good strategies.
0:37:59 > 0:38:02The first one would be shielding spacecraft
0:38:02 > 0:38:04by changing the composition of the walls,
0:38:04 > 0:38:07the thickness of the walls of the spacecraft.
0:38:07 > 0:38:10Water and polyethylene seem to be the best shielding materials.
0:38:10 > 0:38:14The second one is the knowledge of the solar cycle.
0:38:14 > 0:38:16We know that cosmic ray intensity is higher at the part
0:38:16 > 0:38:19of the 11-year solar cycle called solar minimum.
0:38:19 > 0:38:22So if we stay away from solar minimum,
0:38:22 > 0:38:24we can reduce the exposures.
0:38:24 > 0:38:26The last way is the person themself.
0:38:26 > 0:38:28As we learn more about genetic factors,
0:38:28 > 0:38:32we'll be able to find attributes that make a person more resistant
0:38:32 > 0:38:34and more eligible for a long space mission.
0:38:37 > 0:38:39When it comes to future space exploration,
0:38:39 > 0:38:43rocket technology clearly isn't the only challenge.
0:38:43 > 0:38:45Because until we can protect ourselves from cosmic radiation
0:38:45 > 0:38:49in deep space, we may not be going anywhere.
0:38:54 > 0:38:58This is a phenomena we've noticed from the earliest space flights?
0:38:58 > 0:39:02Yeah, it is really weird because it was seen very early on
0:39:02 > 0:39:04and everyone forgot about it.
0:39:04 > 0:39:06We've had sci-fi things
0:39:06 > 0:39:08and we're very familiar with the idea of humans in space.
0:39:08 > 0:39:13No-one ever mentions this, so it's a secret hidden in plain view.
0:39:13 > 0:39:16Yet it is the most common effect, because it's constantly with us.
0:39:16 > 0:39:19Once you get past, is it the magnetic field
0:39:19 > 0:39:21of the Earth that shields us from this?
0:39:21 > 0:39:22It's our great shield.
0:39:22 > 0:39:24That's why we can have life wandering about on the surface
0:39:24 > 0:39:25of our planet.
0:39:25 > 0:39:28It might survive under the oceans if we didn't have a magnetic field
0:39:28 > 0:39:31but up where we are, we need that shield
0:39:31 > 0:39:33because we would be damaged too quickly.
0:39:33 > 0:39:38And there's no chance of building a magnetic field that would surround
0:39:38 > 0:39:42a ship as it travelled to Mars or, indeed, a bio dome when on Mars?
0:39:42 > 0:39:46Well, a very thick lead shielding would do the job but obviously
0:39:46 > 0:39:48to get that into orbit's even harder.
0:39:48 > 0:39:51It's not feasible to shield against.
0:39:51 > 0:39:55Is this the one clear limiting factor on how far we can travel?
0:39:55 > 0:39:58I think it probably is for humans.
0:39:58 > 0:40:01Until we can deal with this or get a medical solution.
0:40:01 > 0:40:05It is yet another reason why humans will never go much beyond Mars,
0:40:05 > 0:40:07even if that far.
0:40:07 > 0:40:10And is there any way in which this man who suggested
0:40:10 > 0:40:12that only fat people go into space,
0:40:12 > 0:40:14that their layers of fat would in some way
0:40:14 > 0:40:18deflect, absorb or somehow...?
0:40:18 > 0:40:20It's true, because fat is largely water
0:40:20 > 0:40:23and water is one of the best materials for absorbing these things.
0:40:23 > 0:40:26The tubbies are coming out as the champions of this.
0:40:26 > 0:40:29It's wishful thinking. You want to volunteer, don't you?
0:40:29 > 0:40:32Don't keep bringing it back to me. I don't know why you're saying that?!
0:40:32 > 0:40:35Just got zinged by the Astronomer Royal.
0:40:35 > 0:40:36Um, OK.
0:40:36 > 0:40:39OK, so what do you actually need to bring with you just to make
0:40:39 > 0:40:42that short hop to the Moon? Let's have a look at the data.
0:40:44 > 0:40:45The Moon is on average:
0:40:50 > 0:40:53To get there you need a ship capable of escaping
0:40:53 > 0:40:57the Earth's gravity and some astronauts made of the right stuff.
0:41:02 > 0:41:04..men and women applied to be astronauts
0:41:04 > 0:41:06for the American space programme
0:41:06 > 0:41:09but selection was strict - both physically and mentally.
0:41:12 > 0:41:14The successful Apollo candidates were, on average:
0:41:22 > 0:41:25Plus they were clever, with an average IQ of...
0:41:28 > 0:41:30Three of the 32 serving astronauts
0:41:30 > 0:41:33were selected for the first trip to the Moon.
0:41:33 > 0:41:35Amongst their luggage were medical supplies,
0:41:35 > 0:41:37survival gear
0:41:37 > 0:41:39and food supplies.
0:41:44 > 0:41:45This is the '60s, remember.
0:41:45 > 0:41:47But the biggest problem isn't the dodgy cuisine,
0:41:47 > 0:41:50it's the escaping Earth's gravity.
0:41:50 > 0:41:53And for a big problem, you need a big rocket.
0:41:53 > 0:41:55The Saturn V was a monster.
0:41:56 > 0:41:58It consisted of three stages.
0:41:58 > 0:42:01First, five F1 engines launched the astronauts.
0:42:01 > 0:42:03The most powerful of their time,
0:42:03 > 0:42:07together they produced 160 million horsepower.
0:42:07 > 0:42:10They burned for 165 seconds and carried the craft 68km.
0:42:12 > 0:42:15A modern family car allows 65mpg.
0:42:16 > 0:42:19Five F1s do about 13cm.
0:42:20 > 0:42:23The second stage takes the spacecraft a further 106km.
0:42:25 > 0:42:29And the third stage takes the craft into orbit.
0:42:29 > 0:42:31And on its way to the Moon.
0:42:33 > 0:42:38Guided by a computer with less power than your average wristwatch.
0:42:38 > 0:42:41The astronauts spent...
0:42:43 > 0:42:45..together in a metal can.
0:42:45 > 0:42:49Just two hours and 32 minutes of which was actually on the Moon.
0:42:49 > 0:42:53They splashed down in the Pacific Ocean considerably lighter than
0:42:53 > 0:42:54when they set off.
0:42:54 > 0:42:58They arrived to a heroes' welcome and three weeks in quarantine.
0:43:05 > 0:43:09It's enormously complicated when we go anywhere in space.
0:43:09 > 0:43:12The huge complication is escaping the gravitational pull of Earth.
0:43:12 > 0:43:14- It is.- You need quite a kick to get off here.
0:43:14 > 0:43:16Many people thought it was impossible.
0:43:16 > 0:43:20Until liquid fuel rockets came along and people thought,
0:43:20 > 0:43:21"My God, those are powerful!
0:43:21 > 0:43:23"They really might get us to the Moon."
0:43:23 > 0:43:26And so, um, what I thought we'd have a go at,
0:43:26 > 0:43:30is seeing quite how easy it is to make a rocket.
0:43:30 > 0:43:32Once you get the hang of the fact
0:43:32 > 0:43:35that liquids have a huge high density of energy in them.
0:43:35 > 0:43:39If you can release that by reacting with an oxidation agent like oxygen
0:43:39 > 0:43:41in the air, it's really surprising.
0:43:41 > 0:43:45The liquid we are using for this is Eastern European vodka.
0:43:45 > 0:43:47How strong a concentration have you got?
0:43:47 > 0:43:48We've searched high and wide
0:43:48 > 0:43:51to find one that's even stronger than last week's show
0:43:51 > 0:43:53and found one that's 96.5% alcohol.
0:43:53 > 0:43:56This is not so much a drink as a rocket fuel, we think.
0:43:56 > 0:43:58- Let's try that.- Where is it from?
0:43:58 > 0:44:01- Is it actually genuinely Polish? - Yes, it is.
0:44:01 > 0:44:02There's debate online over the fact
0:44:02 > 0:44:06that we've claimed various Russian and Balkan vodkas to be -
0:44:06 > 0:44:08- But this is actually Polish.- All vodkas, essentially, are Polish.
0:44:08 > 0:44:11- Except that everyone else is making them.- You're right. OK. Grand.
0:44:11 > 0:44:14I'm not going to step on your heritage at this point!
0:44:14 > 0:44:17I mean, this is essentially pure ethanol,
0:44:17 > 0:44:19and if we put this into a bottle like this,
0:44:19 > 0:44:21it's going to mix with some oxygen,
0:44:21 > 0:44:24and they will combust.
0:44:24 > 0:44:26Now, we're not just going to fire it willy-nilly.
0:44:26 > 0:44:28We have a path for this, by the way.
0:44:28 > 0:44:30I know. It's health and safety gone mad,
0:44:30 > 0:44:34that we're not just going to fire rockets at our audience(!)
0:44:34 > 0:44:35Rockets work on...
0:44:35 > 0:44:38It's Newton's Laws, which is basically, you know,
0:44:38 > 0:44:40the fuel goes that way, so the rocket goes that way.
0:44:40 > 0:44:43- It's action and reaction. - It is action and reaction.
0:44:43 > 0:44:45So you're creating a hot, pressurised gas.
0:44:45 > 0:44:47That goes that way, and that means
0:44:47 > 0:44:50it has to push something that way, and that's your rocket.
0:44:50 > 0:44:52The great thing about these liquid fuels
0:44:52 > 0:44:54is that they have a huge amount of bang for the mass.
0:44:54 > 0:44:56That's the big trick for getting off the planet.
0:44:56 > 0:44:59- I'm ready. Can we have a three, two, one, countdown?- Yeah.
0:44:59 > 0:45:01Five, four, three...
0:45:01 > 0:45:03AUIDENCE JOINS IN ..two, one.
0:45:05 > 0:45:06ROCKET POPS
0:45:06 > 0:45:08LAUGHTER
0:45:10 > 0:45:12See? I mean, as well, if you're going to have a cameraman
0:45:12 > 0:45:15standing directly in line with the rocket...
0:45:15 > 0:45:18Yeah, see, I want to see THAT in slow motion!
0:45:18 > 0:45:20This guy being hit by a rocket!
0:45:20 > 0:45:22Let's see it in slow motion!
0:45:22 > 0:45:25LAUGHTER
0:45:25 > 0:45:26Yeah, let's try it again,
0:45:26 > 0:45:29but with you a foot back, if we can.
0:45:30 > 0:45:31Let's have a countdown.
0:45:31 > 0:45:36ALL: Five, four, three, two, one.
0:45:38 > 0:45:40ROCKET WHOOSHES
0:45:40 > 0:45:43APPLAUSE AND CHEERING
0:45:44 > 0:45:46Very happy with the escape velocity,
0:45:46 > 0:45:48very happy that it returned back down to earth.
0:45:48 > 0:45:50Let's have a look at it in slow motion.
0:45:50 > 0:45:52Let's have a look and see what it looked like.
0:45:52 > 0:45:53OK, ooh, look at that!
0:45:55 > 0:45:57And it returned safely down.
0:45:57 > 0:46:01- Very good. Loving that! - APPLAUSE
0:46:03 > 0:46:04Wow!
0:46:05 > 0:46:07This is a doddle, this business!
0:46:07 > 0:46:09OK, if you've any questions about space travel
0:46:09 > 0:46:11or any ideas you want to chat about,
0:46:11 > 0:46:12we have our After Hours Science Club,
0:46:12 > 0:46:14where an expert in space exploration
0:46:14 > 0:46:16is waiting to answer your questions.
0:46:16 > 0:46:18Just go to the website to get involved,
0:46:18 > 0:46:20or join the conversation on Twitter.
0:46:23 > 0:46:26APPLAUSE
0:46:26 > 0:46:29Professor Rees, every week we ask our esteemed science guests
0:46:29 > 0:46:31to nominate somebody for our Hall Of Fame.
0:46:31 > 0:46:34Generally, a scientific figure from history
0:46:34 > 0:46:35who has been slightly overlooked.
0:46:35 > 0:46:38Who would you like to put into the Hall Of Fame?
0:46:38 > 0:46:40My choice is really not so much a scientist
0:46:40 > 0:46:42as a science-fiction writer.
0:46:42 > 0:46:43Someone called Olaf Stapledon.
0:46:43 > 0:46:46He was actually a lecturer in philosophy at Liverpool,
0:46:46 > 0:46:51but he wrote, in the 1930s, two classic science fiction books.
0:46:51 > 0:46:53One was called Last And First Men,
0:46:53 > 0:46:55and he also wrote another book called Star Maker.
0:46:55 > 0:46:58And Star Maker is a sort of God who creates universes,
0:46:58 > 0:47:01and it's really the first description of the multiverse.
0:47:01 > 0:47:05So he's an amazingly imaginative person who wrote these books.
0:47:05 > 0:47:07They influenced, in particular,
0:47:07 > 0:47:10Arthur C Clarke and Maynard Smith,
0:47:10 > 0:47:12the great biologist.
0:47:12 > 0:47:14And, moreover, I do like to tell my students
0:47:14 > 0:47:17that it's better to read first-rate science fiction
0:47:17 > 0:47:19than second-rate science. DARA LAUGHS
0:47:19 > 0:47:22It's much more interesting, and no more likely to be wrong.
0:47:22 > 0:47:25Fantastic! OK. I genuinely banked somebody in here,
0:47:25 > 0:47:29obviously my first choice would be Samuel Lepkovsky.
0:47:29 > 0:47:32The man who said fat people should go into space.
0:47:32 > 0:47:34But, amazingly, we have no photographs of him.
0:47:34 > 0:47:38It is strange(!) So instead, I'm nominating this man.
0:47:38 > 0:47:40Cosmonaut Gherman Titov.
0:47:40 > 0:47:42He has a lot of firsts to his name.
0:47:42 > 0:47:45He is the first man to spend a day in space,
0:47:45 > 0:47:46the first man to sleep in space,
0:47:46 > 0:47:50first man to take a photograph of the planet from space.
0:47:50 > 0:47:52So all these firsts. Really, the one he's remembered for
0:47:52 > 0:47:55is that he's the first man to suffer from space sickness,
0:47:55 > 0:47:58which is an exaggerated form of air sickness or seasickness,
0:47:58 > 0:48:01caused by the fact that all of your reference points, visually,
0:48:01 > 0:48:03are upside down, while you feel right-side-up.
0:48:03 > 0:48:06It's quite horrendous, and affects people quite badly.
0:48:06 > 0:48:10So that's poor old Gherman Titov. He goes there on the wall.
0:48:10 > 0:48:12Exploration is not just about us heading off into deep space.
0:48:12 > 0:48:15From the comfort of home, we've been scanning the skies
0:48:15 > 0:48:17to see if anything is out there trying to find us.
0:48:17 > 0:48:19And, of course, we'd be privileged and awed
0:48:19 > 0:48:22to discover intelligent life elsewhere in the universe.
0:48:22 > 0:48:24What a momentous event that would be! Or WOULD it?
0:48:46 > 0:48:51They're still out there, sending back signals from 15 billion miles away.
0:48:51 > 0:48:54Voyager 1 is now the furthest man-made object from Earth,
0:48:54 > 0:48:57and is, at any moment, going to leave the solar system.
0:48:57 > 0:48:59And Voyager 2 isn't far behind.
0:49:08 > 0:49:10On board each probe is a golden record
0:49:10 > 0:49:14containing a greeting from Earth and information about humanity,
0:49:14 > 0:49:19should the probes be intercepted by intelligent alien life.
0:49:19 > 0:49:22But should we seek out alien contact anyway?
0:49:22 > 0:49:26What if all ET's interested in is wiping us out?
0:49:35 > 0:49:37Before we even begin to look for ET,
0:49:37 > 0:49:39it might actually be instructive
0:49:39 > 0:49:44to take a look at life on Earth from an evolutionary perspective.
0:49:44 > 0:49:46One of the nice things about biology,
0:49:46 > 0:49:47and evolution, for that matter,
0:49:47 > 0:49:50is that from really rather different starting positions in,
0:49:50 > 0:49:52if you like, the tree of life,
0:49:52 > 0:49:54again and again, the same sort of solution arises.
0:49:58 > 0:50:01So here we are on Steve's stall, and we have the octopus.
0:50:01 > 0:50:04And the fascinating thing about this creature is, at first,
0:50:04 > 0:50:07it looks remarkably alien, but let's look a little bit more closely.
0:50:07 > 0:50:09In particular, let's look at the eyes.
0:50:09 > 0:50:11These eyes, it turns out,
0:50:11 > 0:50:14are constructed in effectively the identical way to our eyes.
0:50:14 > 0:50:16They are known as the camera eye.
0:50:16 > 0:50:19And this gives me some confidence to start with
0:50:19 > 0:50:21that the alien will have not only eyes,
0:50:21 > 0:50:22but for various reasons,
0:50:22 > 0:50:25we can be confident it will be a camera-like eye.
0:50:25 > 0:50:28But the camera-like eye in the octopus has evolved
0:50:28 > 0:50:32completely independently of the camera eye in ourselves.
0:50:32 > 0:50:36'If sophisticated eyes have evolved separately more than once,
0:50:36 > 0:50:38'then what about intelligence?'
0:50:38 > 0:50:40If we look at the way in which brains evolve,
0:50:40 > 0:50:43we see that not only have they become independently large
0:50:43 > 0:50:44in basically unrelated groups -
0:50:44 > 0:50:47parrots, crows, various sorts of ape,
0:50:47 > 0:50:49even the octopus, it so happens -
0:50:49 > 0:50:51but in each case, their cognitive world
0:50:51 > 0:50:52is surprisingly similar to ours.
0:50:52 > 0:50:54It does suggest that, if you like,
0:50:54 > 0:50:57thinking's going to be the same, wherever you are in the galaxy.
0:50:57 > 0:51:00Now this is, of course, guesswork, to some extent.
0:51:00 > 0:51:03Of course it's guesswork, because we only have one Earth,
0:51:03 > 0:51:06one biosphere, so far as we know, a single origin of life.
0:51:06 > 0:51:09In fact, many astrobiologists believe
0:51:09 > 0:51:12that we'll detect life on other worlds
0:51:12 > 0:51:13within the next few decades.
0:51:15 > 0:51:18And it's probably reasonable to assume that natural selection
0:51:18 > 0:51:22as an evolutionary driver, is a universal principle,
0:51:22 > 0:51:26that will be at work wherever there's life in the cosmos.
0:51:26 > 0:51:30So it follows that intelligence, if the conditions are right,
0:51:30 > 0:51:33will exist on some remote world.
0:51:38 > 0:51:39In California,
0:51:39 > 0:51:42at the Search For Extraterrestrial Intelligence Institute,
0:51:42 > 0:51:44senior astronomer Seth Shostak
0:51:44 > 0:51:47is leading the search further out in the galaxy.
0:51:53 > 0:51:55It's nice to see you.
0:51:55 > 0:51:57BEAM-ME-UP NOISE
0:51:57 > 0:51:59Seth, how convinced are you that intelligent life
0:51:59 > 0:52:01exists out there somewhere?
0:52:01 > 0:52:04All we can say is, yes, we haven't found ET yet.
0:52:04 > 0:52:06I remain optimistic that that might happen
0:52:06 > 0:52:08in the next couple of decades.
0:52:08 > 0:52:11But if this is the only place, even in our galaxy,
0:52:11 > 0:52:12where there's not just life,
0:52:12 > 0:52:14but life that's fairly clever,
0:52:14 > 0:52:17then that makes us a miracle.
0:52:17 > 0:52:20And, you know, after looking at 500 years of astronomical history,
0:52:20 > 0:52:23I'm disinclined to believe in miracles.
0:52:26 > 0:52:30The thing is, our history on Earth is littered with episodes of contact
0:52:30 > 0:52:32between intelligent civilisations
0:52:32 > 0:52:35that were essentially alien to one another.
0:52:35 > 0:52:39And more often than not, it's ended badly for one of the cultures.
0:52:39 > 0:52:42The more technologically advanced usually triumphs.
0:52:42 > 0:52:44Violence is depressingly common.
0:52:48 > 0:52:52But who's to say that aliens would be as aggressive as people anyway?
0:53:00 > 0:53:03It's quite possible that aliens could be
0:53:03 > 0:53:05very highly competitive and aggressive,
0:53:05 > 0:53:10and unlike many Americans, I firmly endorse the theory of evolution,
0:53:10 > 0:53:12and there IS a survival of the fittest.
0:53:12 > 0:53:15But what happens as you move up the scale,
0:53:15 > 0:53:18the definition of the "fittest" can change.
0:53:18 > 0:53:20Tell me a bit more about that.
0:53:20 > 0:53:26Remember, they had to survive for possibly many millions of years,
0:53:26 > 0:53:29and you can't do that in a state of perpetual conflict.
0:53:29 > 0:53:31From what I can tell,
0:53:31 > 0:53:34from political science, sociology, and psychology,
0:53:34 > 0:53:36we're shifting in the direction
0:53:36 > 0:53:40of more peaceable, pro-social kinds of behaviours.
0:53:44 > 0:53:47There are billions of stars out there,
0:53:47 > 0:53:50and probably an even bigger number of planets.
0:53:50 > 0:53:55It's not unreasonable to expect that some form of alien life IS out there.
0:53:55 > 0:53:57The chances of us finding them,
0:53:57 > 0:54:00or them finding us, are actually very small.
0:54:00 > 0:54:06And even if contact was made, any conversation would be painfully slow.
0:54:06 > 0:54:09So, should we be afraid of aliens?
0:54:09 > 0:54:11Well, human beings have always been curious
0:54:11 > 0:54:13about the world and the universe,
0:54:13 > 0:54:17and that curiosity has led us to some of our greatest advances.
0:54:17 > 0:54:20It strikes me that, if we found evidence of alien life,
0:54:20 > 0:54:23why would we not want to contact them?
0:54:23 > 0:54:25Explorers launch into the unknown.
0:54:25 > 0:54:28We deal with the consequences later.
0:54:28 > 0:54:31SENSOR BEEPS
0:54:40 > 0:54:43APPLAUSE
0:54:46 > 0:54:49So, Alok, fresh from killing the pandas last week,
0:54:49 > 0:54:51this week you want to kill ET as well.
0:54:51 > 0:54:55Is this really our choice anyway? Whether we communicate with aliens?
0:54:55 > 0:54:58There's two points here. One is, why wouldn't you?
0:54:58 > 0:54:59I mean, wouldn't you want to?
0:54:59 > 0:55:02It just seems a really strange thing to do,
0:55:02 > 0:55:05to know that there's intelligent life out there, or even A life,
0:55:05 > 0:55:07and think, "You know what, let's just not bother."
0:55:07 > 0:55:09The second thing I think's interesting is,
0:55:09 > 0:55:11and a big-up here to Charles Darwin, of course,
0:55:11 > 0:55:14the idea of evolution by natural selection,
0:55:14 > 0:55:16the idea that it is the thing that we expect will happen.
0:55:16 > 0:55:18It doesn't matter what these chemicals you start with.
0:55:18 > 0:55:22We can pretty much guess intelligently
0:55:22 > 0:55:25what these life forms might do, how they might behave.
0:55:25 > 0:55:27I think it's magnificent proof that,
0:55:27 > 0:55:30actually, he had such a great idea back then.
0:55:30 > 0:55:33We already know how to search for exoplanets.
0:55:33 > 0:55:35We have Kepler out there searching all the time.
0:55:35 > 0:55:37We also know what to look for,
0:55:37 > 0:55:40what are the tell-tale signs of there being life on the planet.
0:55:40 > 0:55:43Well, it's very exciting, because until 15 years ago,
0:55:43 > 0:55:46we didn't know anything about planets around other stars.
0:55:46 > 0:55:49Now we know that most stars have planets around them,
0:55:49 > 0:55:51many planets, like the Earth.
0:55:51 > 0:55:54So lots of possible sites for life to develop.
0:55:54 > 0:55:57We don't yet know if there is life in any of those planets,
0:55:57 > 0:55:58but in 10-20 years, I think,
0:55:58 > 0:56:00by observing these planets carefully,
0:56:00 > 0:56:01we'll be able to see
0:56:01 > 0:56:04if they've got oxygen and things like that.
0:56:04 > 0:56:08But also, I think we mustn't be too anthropocentric,
0:56:08 > 0:56:10because, despite what Simon Morris says,
0:56:10 > 0:56:12it could be there's another kind of life
0:56:12 > 0:56:14based on quite different chemistry
0:56:14 > 0:56:15and it could be, of course,
0:56:15 > 0:56:17that it's much more advanced than us.
0:56:17 > 0:56:20Because, after all, we are just a stage in life on Earth.
0:56:20 > 0:56:23In the future, there's going to be different kinds of life,
0:56:23 > 0:56:27either genetically modified versions of humans, or maybe machines.
0:56:27 > 0:56:30And anything out there may be at this more advanced stage.
0:56:30 > 0:56:34So I think we should be very open-minded about what we look for.
0:56:34 > 0:56:37Are you confident that there is alien life?
0:56:38 > 0:56:41No. I mean, I think we can't bet, because we don't know
0:56:41 > 0:56:44how likely it was for life to get started here on the Earth.
0:56:44 > 0:56:46We don't understand that.
0:56:46 > 0:56:48That's a basic problem for all biologists,
0:56:48 > 0:56:51and we don't know how it would evolve.
0:56:51 > 0:56:54But I think it's worth the search.
0:56:54 > 0:56:57Also, I think it would be great to find any evidence of life,
0:56:57 > 0:57:00but also, of course, if it's not there,
0:57:00 > 0:57:01then that has an upside too,
0:57:01 > 0:57:04because we can then be less cosmically modest.
0:57:04 > 0:57:06We can say that, even though
0:57:06 > 0:57:09the Earth is a tiny speck in this huge cosmos,
0:57:09 > 0:57:13it could be the only place in the galaxy where life has evolved.
0:57:13 > 0:57:15- By the way... - PLANE ROARS OUTSIDE STUDIO
0:57:15 > 0:57:19Oh, we'll wait until the giant, low-flying plane passes overhead!
0:57:19 > 0:57:20Man, it would be ironic
0:57:20 > 0:57:25if an alien invasion started just as we were sitting here discussing it!
0:57:25 > 0:57:31I would laugh if we were all marched into slavery by our alien overlords!
0:57:31 > 0:57:34Let's see how our 3D printer has done.
0:57:34 > 0:57:36Mark, do you have the result of that there?
0:57:36 > 0:57:38Yeah, hold on. I'll bring it over.
0:57:38 > 0:57:39Lovely stuff.
0:57:39 > 0:57:42Now, this may seem tiny and incidental and unimpressive,
0:57:42 > 0:57:45but nonetheless, printed during the run of the show,
0:57:45 > 0:57:47maybe started a little bit beforehand.
0:57:47 > 0:57:49It is what you would need on the moon, which is, of course,
0:57:49 > 0:57:51a Science Club...
0:57:51 > 0:57:53what is this, exactly?
0:57:53 > 0:57:55- LAUGHTER - It's a Frisbee!
0:57:55 > 0:57:58I thought it was a coaster!
0:57:58 > 0:58:00With all of this technology, to build a drinks holder!
0:58:00 > 0:58:03In space, if you throw a Frisbee and fail to catch it, it's gone.
0:58:03 > 0:58:06It's off into the next galaxy. You have to print another one.
0:58:06 > 0:58:09Thank you very much for that, Mark Miodownik,
0:58:09 > 0:58:12as well as reporters, Dr Helen Czerski and Alok Jha,
0:58:12 > 0:58:16and Josh Widdicombe, of course, who came with Dr Iya Whiteley,
0:58:16 > 0:58:20and our major guest tonight, please thank Prof Martin Rees.
0:58:20 > 0:58:23APPLAUSE
0:58:25 > 0:58:26But what can we take from tonight?
0:58:26 > 0:58:28In the old days, to become an astronaut,
0:58:28 > 0:58:30you had to have the "right stuff",
0:58:30 > 0:58:33Fighter pilot, square-jawed, all-American hero.
0:58:33 > 0:58:37It turns out, what we actually need are astronauts who are old,
0:58:37 > 0:58:40don't mind the smell of poo, have no real reason to come home again,
0:58:40 > 0:58:42but most of all, are fat enough
0:58:42 > 0:58:45to live without food for three months at a time.
0:58:45 > 0:58:46The door's open to all of us!
0:58:46 > 0:58:48From everybody here at Science Club, goodnight.
0:58:48 > 0:58:51APPLAUSE
0:59:00 > 0:59:04# And I'm floating like God in his heaven
0:59:04 > 0:59:08# High in the stratosphere
0:59:08 > 0:59:12# Don't come quick, you can see our house from here... #
0:59:12 > 0:59:15Subtitles by Red Bee Media Ltd
0:59:15 > 0:59:17# Floating like God in his heaven. #