0:00:06 > 0:00:13Out there, hidden from the naked eye, is a universe we barely understand.
0:00:13 > 0:00:16There are stars being born,
0:00:16 > 0:00:22black holes, perhaps even new forms of life...
0:00:22 > 0:00:28But now, astronomers are able to see the cosmos as never before.
0:00:31 > 0:00:36They are creating a new breed of super-telescope of unprecedented power and clarity.
0:00:36 > 0:00:43We have, at our disposal, tools that have never existed before in the history of mankind.
0:00:43 > 0:00:46We're the first ones to get to look at this,
0:00:46 > 0:00:49you know you don't actually realise how special a time this is.
0:00:51 > 0:00:58This revolution in telescope construction promises a new age of discovery.
0:00:58 > 0:01:03Right now is an extremely exciting time to be an astronomer, to be an engineer
0:01:03 > 0:01:07building telescopes, because the questions keep multiplying.
0:01:07 > 0:01:11The answers keep coming too, but the questions come even faster than the answers.
0:01:19 > 0:01:22Engines start at 7.15, we'll taxi out at 7.25.
0:01:22 > 0:01:26At the ends of the Earth, astronomers are trying to capture
0:01:26 > 0:01:32light that has travelled from the farthest reaches of space.
0:01:32 > 0:01:36So we're taking it to the Chajnantor Plateau.
0:01:36 > 0:01:40The air density's about 50% of that at sea level.
0:01:40 > 0:01:44So gloves on, hat on, oxygen happening...
0:01:44 > 0:01:48more or less ready for the Chilean desert.
0:01:48 > 0:01:54Together, they are reinventing what a telescope is and what it can do.
0:01:54 > 0:01:58And they are rewriting the story of the universe.
0:02:10 > 0:02:13The Atacama Desert, Chile.
0:02:26 > 0:02:31Hardly any vegetation, moisture or life.
0:02:34 > 0:02:39Mountains here have received no rain in living memory.
0:02:40 > 0:02:47They reach up over one and a half miles into dry, cloudless skies.
0:02:47 > 0:02:53Throughout history only death awaited those who ventured here.
0:02:53 > 0:02:55Until now...
0:03:12 > 0:03:15This is La Residencia.
0:03:18 > 0:03:20But this is no luxury hotel...
0:03:20 > 0:03:25and the people here no ordinary tourists.
0:03:25 > 0:03:28This is the desert home from home for astronomers
0:03:28 > 0:03:34hunting for the most mysterious and elusive objects in the Universe.
0:03:34 > 0:03:39It's very exciting to be out here in the desert, and what we are actually doing here is,
0:03:39 > 0:03:43we are looking for a very particular object in our own galaxy, we're looking for a black hole.
0:03:46 > 0:03:50To locate this black hole, astronomers will be using
0:03:50 > 0:03:53one of the most powerful telescopes ever built...
0:03:59 > 0:04:04..the VLT - the very large telescope.
0:04:08 > 0:04:15This, quite simply, is the most advanced optical instrument ever constructed.
0:04:21 > 0:04:26The VLT is made up of four main telescopes.
0:04:28 > 0:04:32Each contains identical glass ceramic mirrors -
0:04:32 > 0:04:34the largest ever manufactured.
0:04:36 > 0:04:41This is what it takes to spot a black hole.
0:04:50 > 0:04:54But it's not going to be easy, even with the VLT.
0:04:54 > 0:04:56A black hole...
0:04:56 > 0:04:58the dense remains of a dead star...
0:04:58 > 0:05:04has such a strong gravitational pull that nothing can escape... even light.
0:05:04 > 0:05:07A black hole collects all the light
0:05:07 > 0:05:10so from a certain distance from the black hole
0:05:10 > 0:05:11no light can escape any more,
0:05:11 > 0:05:15so in that sense you cannot observe a black hole, because it's black.
0:05:16 > 0:05:21To locate it, astronomers will be searching for clues in infrared light...
0:05:21 > 0:05:25light which lies just outside the visible part of the spectrum.
0:05:25 > 0:05:29It is why the VLT is in the Atacama.
0:05:30 > 0:05:34You need the most advanced facilities to observe this
0:05:34 > 0:05:37and to do so, um, you need also very certain sites
0:05:37 > 0:05:41that are dry for example and so this desert here
0:05:41 > 0:05:45is just the perfect place for such research.
0:05:45 > 0:05:48Dry air is vital...
0:05:48 > 0:05:54atmospheric moisture filters out infrared light coming from space.
0:05:54 > 0:05:58By building their telescope above the clouds on a desert mountain top,
0:05:58 > 0:06:02astronomers hope for the clearest possible view.
0:06:15 > 0:06:18It's now late afternoon.
0:06:18 > 0:06:24Inside the four telescopes, engineers are preparing for the coming night's observations.
0:06:31 > 0:06:35These 23-ton mirrors are fully automated...
0:06:35 > 0:06:39and will be programmed in advance.
0:06:39 > 0:06:45This 530 square-foot surface can observe objects
0:06:45 > 0:06:49four billion times fainter than can be seen with the naked eye...
0:06:49 > 0:06:52ideal for finding a distant black hole...
0:06:57 > 0:07:03As the engineering shift ends, the black hole hunters' shift begins.
0:07:03 > 0:07:08Gunther and his colleague Andreas will be working through to dawn.
0:07:08 > 0:07:13To find the black hole, they need still, clear dry skies...
0:07:13 > 0:07:18and this appears to be the perfect spot.
0:07:27 > 0:07:31These are the clearest skies on Earth.
0:07:36 > 0:07:41Here tens of thousands of stars can be seen twinkling overhead.
0:07:45 > 0:07:50But if you're looking for a black hole this represents a problem...
0:07:50 > 0:07:55Because in space, stars don't twinkle...
0:08:01 > 0:08:07To find the black hole, the astronomers in the control room have to get rid of this distortion.
0:08:09 > 0:08:14So what we see here is a stellar image and we see it hopping back and forth,
0:08:14 > 0:08:17and that is because the light from the star, comes to us,
0:08:17 > 0:08:18through the atmosphere of the Earth.
0:08:18 > 0:08:23And we would like to ideally get rid entirely of this motion.
0:08:27 > 0:08:32Here at the VLT, engineers have devised a way of doing this.
0:08:39 > 0:08:45In the heart of the telescope they prepare to create a star of their own.
0:08:45 > 0:08:51It will be used to calculate how atmospheric distortion affects the view of space.
0:08:54 > 0:08:58A laser is fired into the upper atmosphere.
0:09:00 > 0:09:03It interacts with sodium atoms,
0:09:03 > 0:09:08creating an artificial star 60 miles above the desert.
0:09:08 > 0:09:11The ever-shifting image of the artificial star
0:09:11 > 0:09:15is used to constantly correct the telescope optics
0:09:15 > 0:09:19to create a stable view through the moving atmosphere.
0:09:25 > 0:09:31Back in the control room, the black-hole hunters are still hard at work.
0:09:31 > 0:09:36Theirs is a world fuelled by strong coffee.
0:09:36 > 0:09:42Yes, to be here at, 4.30 local time, in the morning, is very exciting.
0:09:42 > 0:09:47Er, because, um, this is what it is about to be an astronomer.
0:09:47 > 0:09:50We are sitting here looking at the phenomenon we are interested in
0:09:50 > 0:09:55and of course you have to go home to analyse your data, and to interpret the data.
0:09:55 > 0:09:57And to try to understand what is going on.
0:09:57 > 0:10:00But beyond that, you know, you simply see the phenomena.
0:10:00 > 0:10:02And that is what all the excitement is about.
0:10:02 > 0:10:07It might look like any other office, but here they're closing in on one
0:10:07 > 0:10:12of the most powerful and elusive objects in space.
0:10:12 > 0:10:16So here we have an image of the central region of the galaxy,
0:10:16 > 0:10:23and it's actually taken in the infrared, its size is about 300 by 100 light years.
0:10:23 > 0:10:28The stellar density is highest here, this is where the heart of the Milky Way is located,
0:10:28 > 0:10:33that's what we're interested in, and we can now zoom into this region,
0:10:33 > 0:10:38and this is actually a slice taken at the centre of the galaxy.
0:10:38 > 0:10:43Over here you see a small cluster of high velocity stars,
0:10:43 > 0:10:46they are orbiting this spot here.
0:10:46 > 0:10:50These orbiting stars emit vast quantities of gas.
0:10:50 > 0:10:58And it's the behaviour of this gas that holds the key to the location of the black hole.
0:10:58 > 0:11:01If we have a massive black hole and gas coming towards it, it's going to
0:11:01 > 0:11:06be accreted around the black hole and may form a so-called accretion disk.
0:11:06 > 0:11:10So this is then hot gas orbiting the massive black hole.
0:11:10 > 0:11:15So the light coming from that region, tell to us astronomers this actually here,
0:11:15 > 0:11:17at the centre of the Milky Way,
0:11:17 > 0:11:21this object is the location of a massive black hole.
0:11:26 > 0:11:30It's a clever piece of detective work.
0:11:30 > 0:11:38This insignificant-looking dot pinpoints the supermassive black hole at the very heart of our own galaxy.
0:11:41 > 0:11:43It might not look like much
0:11:43 > 0:11:51but these few pixels in reality cover an area about 27 million miles across.
0:11:51 > 0:11:57The black hole they orbit is thought to be four million times heavier than our own Sun.
0:11:59 > 0:12:05Well, studying black holes and doing astro physics, brings you basically to the limits of understanding.
0:12:05 > 0:12:10It brings you to the limits of how we can describe the world that we're living in.
0:12:14 > 0:12:19So in the process of understanding our world, telescopes are very important,
0:12:19 > 0:12:24because they basically represent the eyes with which we look at the universe.
0:12:27 > 0:12:31It's 7am, and the astronomers head down the mountain.
0:12:33 > 0:12:38The power and optical resolution of these new supertelescopes
0:12:38 > 0:12:41are revealing a previously invisible universe.
0:12:56 > 0:13:00How many cups of coffee do you think you drank last night?
0:13:02 > 0:13:09Um, indeed when one stays up so long, uh, one has to maintain your concentration
0:13:09 > 0:13:15and so coffee is a good way to do so, so I had four or five cups of strong coffee.
0:13:16 > 0:13:19First of all, I'm very happy because, uh, not only
0:13:19 > 0:13:22the weather was very good now, but we also could see the black hole.
0:13:25 > 0:13:29That was a very successful night, yes. It was exactly what we wanted.
0:13:29 > 0:13:32Tired, Andreas?
0:13:32 > 0:13:35Yeah. I'm actually tired.
0:13:35 > 0:13:39So, I'm looking forward to having this breakfast and then go to bed.
0:13:39 > 0:13:45Few people come off shift having seen the supermassive black hole at the centre of our galaxy.
0:13:45 > 0:13:48Just over a decade ago such observations would
0:13:48 > 0:13:53have been impossible as telescopes like the VLT simply didn't exist.
0:13:57 > 0:14:01At 8,600 feet on top of this desert mountain
0:14:01 > 0:14:06the VLT can capture vast amounts of infrared light from space.
0:14:06 > 0:14:08But not all of it.
0:14:11 > 0:14:16The atmosphere filters out the rest, even up here in this dry air.
0:14:20 > 0:14:24To capture this missing light, astronomers have to get their
0:14:24 > 0:14:28telescopes higher than this mountain top.
0:14:28 > 0:14:30Much higher.
0:14:33 > 0:14:36Palmdale, California.
0:14:38 > 0:14:43If it's altitude you're after, there are few better place to come than here.
0:14:45 > 0:14:51Flight 58. Another ten-hour jaunt Northwestern United States tonight.
0:14:51 > 0:14:55It's the beginning of a long night for astronomer Professor Terry Herter.
0:15:05 > 0:15:11Engines start at 7.15. We'll taxi out at 7.25 and take-off is planned for 7.45
0:15:11 > 0:15:14and we'll land at approximately 6am.
0:15:16 > 0:15:19- Aircraft status?- Good, it's fuelled.
0:15:19 > 0:15:22We do have the crew oxygen issue, but it's been checked.
0:15:30 > 0:15:32Tonight, Terry and his team
0:15:32 > 0:15:36will be trying to look inside distant nebulae...
0:15:36 > 0:15:40the cosmic dust clouds where stars are born and die.
0:15:40 > 0:15:47OK, so we're going to start with an old friend we've already observed this on a couple of flights.
0:15:47 > 0:15:51This is Frosty Leo. This is a nebula in the Constellation Leo.
0:15:51 > 0:15:53It's known as a Frosty Leo as it's got
0:15:53 > 0:15:57ice lines at 43 and 63 microns.
0:15:59 > 0:16:06To see into these mysterious places, the team will be hunting for infrared light.
0:16:06 > 0:16:12Unlike visible light, infrared can escape the dust that shrouds a nebula.
0:16:14 > 0:16:18But to capture this light requires a most unusual telescope.
0:16:28 > 0:16:29Meet SOFIA.
0:16:31 > 0:16:35Suffice to say, this is no ordinary jumbo jet.
0:16:38 > 0:16:43This plane has been given a one billion-dollar makeover.
0:16:43 > 0:16:48What began as a conventional airliner is now the world's largest mobile
0:16:48 > 0:16:53astronomical observatory, with an infrared telescope beneath the bulge.
0:16:53 > 0:16:57That's all I got. Let's go! Thank you.
0:16:57 > 0:16:59It's now late afternoon.
0:17:02 > 0:17:07This is only the third major research observation flight for the team.
0:17:14 > 0:17:19This is the first ever mission to be filmed for television.
0:17:20 > 0:17:25On board, technicians are completing their preparations.
0:17:25 > 0:17:31To capture the faintest infrared light they have to overcome a significant challenge.
0:17:33 > 0:17:37They have to stop the telescope from observing itself.
0:17:37 > 0:17:43When you operate in the infrared part of the spectrum, everything around you emits light.
0:17:43 > 0:17:45And for our instrument to detect light from space,
0:17:45 > 0:17:48we have to prevent it from basically seeing itself.
0:17:50 > 0:17:53It emits light itself if it isn't very cold.
0:17:53 > 0:17:58So essentially the colder something is, the less light it emits.
0:18:04 > 0:18:11By super-cooling the telescope, the technicians will prevent it from blurring its own images.
0:18:11 > 0:18:15They are making it about as cold as is scientifically possible.
0:18:20 > 0:18:22Our instrument is actually being cooled down
0:18:22 > 0:18:25to a temperature just four degrees above absolute zero,
0:18:25 > 0:18:31about minus 273 degrees centigrade. Very, very cold.
0:18:36 > 0:18:42With the telescope now cryogenically cooled, the team are getting close to take-off.
0:18:42 > 0:18:49For Terry, it's a unique role - no other observatory like this exists.
0:18:49 > 0:18:52Airborne observing is rather unique.
0:18:52 > 0:18:55It's hard to explain quite how different it is to an astronomer
0:18:55 > 0:18:58who's never been in this, been in this seat.
0:18:58 > 0:19:04You don't want to waste any time, we're in the air burning fuel, you want to be as efficient as you can.
0:19:04 > 0:19:07It's sort of funny, I don't get to worry about what goes right
0:19:07 > 0:19:10usually, I'm worried about what's going wrong and how can I fix it.
0:19:17 > 0:19:21By 7pm SOFIA is ready for take-off.
0:19:22 > 0:19:27For the next 11 hours the team will be flying an arc-shaped course
0:19:27 > 0:19:32as their celestial targets move across the sky with Earth's rotation.
0:19:32 > 0:19:34'Three, two, one...'
0:19:39 > 0:19:45'NASA 747 heavy contact Los Angeles, 127.1. You have a good flight!'
0:20:01 > 0:20:07This mission is taking SOFIA far higher than jumbo jets usually fly.
0:20:13 > 0:20:19SOFIA and her 17 ton-telescope is heading for the stratosphere.
0:20:21 > 0:20:23132.6.
0:20:32 > 0:20:36Here, nearly eight miles above the planet,
0:20:36 > 0:20:41she will be above 99% of the water and gases in the atmosphere.
0:20:43 > 0:20:46At this altitude, the star hunters can make infrared observations
0:20:46 > 0:20:51which are impossible for ground-based telescopes.
0:20:51 > 0:20:54This is, er, what shall I say? This is eye candy
0:20:54 > 0:20:56for scientists that we're dealing with.
0:20:59 > 0:21:06Tonight, the team are searching for infrared light telling the story of the origin and destiny of stars.
0:21:09 > 0:21:15So we're actually looking at the case where a star is dying, and throwing out stuff away
0:21:15 > 0:21:20from it. And so we're looking at the...what's called an outflow, or the dying stage of a star.
0:21:22 > 0:21:26It's crucial research.
0:21:26 > 0:21:31The way stars die will influence those born in their place.
0:21:31 > 0:21:35The dots we're seeing on the screen right now is a star which is dying,
0:21:35 > 0:21:37OK, the name of it is Frosty Leo.
0:21:37 > 0:21:41It's called Frosty Leo because there's actually water ice associated with it.
0:21:41 > 0:21:42So Frosty.
0:21:42 > 0:21:49The specific nature of this research is what makes SOFIA's capabilities so important.
0:21:49 > 0:21:56Detecting water out among the stars is actually not as easy as you might think.
0:21:56 > 0:22:01It's very abundant, but because our atmosphere has so much water in it, it's hard to actually observe.
0:22:01 > 0:22:06So that's why we're in an aeroplane above this, so we can detect some of those types of objects.
0:22:06 > 0:22:10But the technical challenges don't end here.
0:22:12 > 0:22:15Observing dying stars thousands of light years away
0:22:15 > 0:22:20from the back of a moving aeroplane is easier said than done.
0:22:20 > 0:22:25It requires the most sophisticated engineering.
0:22:25 > 0:22:30This telescope is actually quite amazing, in the sense that we are flying in an aeroplane which
0:22:30 > 0:22:33moves through the atmosphere, which shakes up and down and moves around.
0:22:33 > 0:22:37But it can track on the sky and point to an object, and keep it fixed there,
0:22:37 > 0:22:39with tremendous accuracy.
0:22:41 > 0:22:46Once locked onto a celestial target, the telescope stays steady.
0:22:49 > 0:22:53This isn't the telescope moving inside the plane
0:22:53 > 0:22:56but the plane moving around the telescope.
0:23:03 > 0:23:08Navigating this flying telescope is a unique challenge.
0:23:08 > 0:23:11So we're going to go this way until we get to San Antonio, Texas.
0:23:11 > 0:23:17As the Earth rotates, the apparent position of their celestial target is constantly changing.
0:23:17 > 0:23:20They have to ensure SOFIA is always in the right spot to see it.
0:23:20 > 0:23:24People ask, "Where, are you flying tonight? "And I say, "I don't know.
0:23:24 > 0:23:25"The United States."
0:23:27 > 0:23:33Right now to let you know exactly where the aeroplane is, we are at 41,000 feet,
0:23:33 > 0:23:39we are flying at point 0.85 mach, about 550 miles an hour and,
0:23:39 > 0:23:44right now we're just over Jackson Hole, Wyoming and, er we're heading on a south-easterly heading
0:23:44 > 0:23:51along our desired track to keep the celestial body of interest in the field view of the telescope.
0:23:51 > 0:23:55It's now four o'clock in the morning.
0:23:55 > 0:23:58Back in economy class the astronomers have observed
0:23:58 > 0:24:02a stellar nursery in the direction of the constellation Cassiopeia.
0:24:02 > 0:24:06What we're looking at here is a region where new stars are being born.
0:24:06 > 0:24:12This region is a little over probably about 2,000 light years from us
0:24:12 > 0:24:16in distance so we're looking at it in back about the time of the Romans,
0:24:16 > 0:24:19that's when the light originated from here.
0:24:21 > 0:24:24And what we see here are not only the stars themselves but there is
0:24:24 > 0:24:29gas and dust left over from the birth of the stars.
0:24:29 > 0:24:34This dust provides a crucial clue to how new stars might form.
0:24:34 > 0:24:38The important part about this is basically that
0:24:38 > 0:24:42the stars themselves when they're born affect their environment,
0:24:42 > 0:24:46which in turn affects the next generation of stars.
0:24:46 > 0:24:53And so this may help to create other stars in the area being born, or it may actually help
0:24:53 > 0:24:55to keep them from being formed.
0:24:59 > 0:25:00'NASA 747 full stop.'
0:25:00 > 0:25:01That's affirmative.
0:25:01 > 0:25:06Observing a distant nebula during a bumpy night-flight
0:25:06 > 0:25:11in the back of a jumbo jet is a remarkable achievement.
0:25:13 > 0:25:20SOFIA doesn't have the magnification power of the VLT, yet her ability to reach the stratosphere
0:25:20 > 0:25:27means that she can capture certain infrared wavelengths that never make it to the ground.
0:25:32 > 0:25:36But just like the VLT, she will never capture a complete picture
0:25:36 > 0:25:43even at 41,000 feet infrared light coming from space can't be seen in its full intensity.
0:25:43 > 0:25:49To observe this, astronomers have to take their telescopes to the final frontier.
0:25:51 > 0:25:54'Three, two, one...'
0:25:54 > 0:25:57April 24th 1990.
0:25:57 > 0:25:59'Lift off of the Space Shuttle Discovery'
0:26:04 > 0:26:08NASA's newest, most ambitious space telescope was launched.
0:26:08 > 0:26:11'One minute thirty seconds into the flight.
0:26:11 > 0:26:18'13 miles in altitude, 50 miles down range, travelling at almost 2,000 miles per hour.
0:26:18 > 0:26:25Hubble was transported to near Earth orbit, 347 miles above the planet.
0:26:35 > 0:26:41And it's still up there, sending back images that have changed our view of the universe.
0:26:43 > 0:26:46But all this so nearly never happened.
0:26:50 > 0:26:54After launch, Hubble's mirror was found to be faulty...
0:26:54 > 0:26:58a problem only solved with repairs made from the space shuttle.
0:27:01 > 0:27:03The inspiration and lessons
0:27:03 > 0:27:06learned from Hubble couldn't be clearer for engineers in Los Angeles.
0:27:08 > 0:27:14They're working on one of the most advanced telescopes ever - the James Webb Space Telescope,
0:27:14 > 0:27:19possibly the ultimate exploration machine.
0:27:21 > 0:27:27It will take infrared pictures to probe the biggest cosmological questions.
0:27:27 > 0:27:30How do galaxies actually form,
0:27:30 > 0:27:32how do they form those spiral shapes?
0:27:32 > 0:27:33We don't know why.
0:27:33 > 0:27:38Could life evolve in other places in the solar system?
0:27:38 > 0:27:43Could life evolve in other places in the galaxy or in the universe?
0:27:43 > 0:27:48Is there other life out there? I mean, how much bigger can you get than answering that question?!
0:27:48 > 0:27:52The team's ambition is breathtaking.
0:27:52 > 0:27:57But if controversies over the 6.5bn price tag
0:27:57 > 0:28:03don't derail the project, their greatest discoveries might be those they least expect...
0:28:03 > 0:28:06Certainly with the Hubble space telescope, the things that
0:28:06 > 0:28:10we said, the reasons why we should do it and what we would find,
0:28:10 > 0:28:16what we actually found blew the doors off anything that we had imagined before.
0:28:16 > 0:28:19And with James Webb telescope, we're just creating a capability,
0:28:19 > 0:28:23we're opening a door to view the cosmos that could never be opened any other way.
0:28:26 > 0:28:31This time though there will be no second chances if things go wrong...
0:28:31 > 0:28:33All right, are you guys ready?
0:28:35 > 0:28:39Just watch out, all the edges. And make sure you're pulling correctly.
0:28:39 > 0:28:42And just stop if you see anything, OK?
0:28:42 > 0:28:46Because once launched, the telescope and its distinctive
0:28:46 > 0:28:523,200 square foot sun shield will be completely beyond reach.
0:28:55 > 0:28:58The James Webb space telescope is actually being put in an orbit
0:28:58 > 0:29:05at what we call an L2 orbit, or a Lagrange two orbit, and basically this is a point in space,
0:29:05 > 0:29:08it's about a million miles away from Earth.
0:29:08 > 0:29:11We're talking a long way away, we can't get to this one.
0:29:13 > 0:29:16The telescope and its reflective sun shield will be located at the L2 point
0:29:16 > 0:29:23so as to be far removed from sources of infrared light, which might blur its pictures.
0:29:26 > 0:29:31The sun shield should protect the telescope from any infrared energy that remains.
0:29:34 > 0:29:38What you're seeing here is one layer of the sun shield.
0:29:38 > 0:29:42When it deploys out, it's about the size of a tennis court, but the thickness of it
0:29:42 > 0:29:48is only about the thickness of a human hair, which is about one to two thousandths of an inch.
0:29:48 > 0:29:53The finished product will consist of five layers, each coated
0:29:53 > 0:29:57with silicon to reflect infrared energy away from the optics.
0:29:59 > 0:30:02Nothing like this telescope has ever been attempted.
0:30:02 > 0:30:06But perhaps even more remarkable is that the team behind it
0:30:06 > 0:30:10aren't entirely sure what it might discover.
0:30:10 > 0:30:14I think what's really amazing is that you build this instrument,
0:30:14 > 0:30:17you invent all these new technologies,
0:30:17 > 0:30:21you have some of the most amazing people in the world contributing,
0:30:21 > 0:30:24and once you have this instrument operating in space,
0:30:24 > 0:30:27you have no idea what you're going to find.
0:30:28 > 0:30:32I think it's fair to say that telescopes open up the unexpected.
0:30:32 > 0:30:36That's the main reason we're sending this up there,
0:30:36 > 0:30:39is to see what we don't know is out there.
0:30:39 > 0:30:43We can never predict the magnitude of discoveries we can make as we go
0:30:43 > 0:30:47and open up previously closed doors into the cosmos, into astronomy.
0:30:47 > 0:30:52We're expecting to see the formation of stars, and galaxies,
0:30:52 > 0:30:56and first light, and we have an idea of what this might look like,
0:30:56 > 0:30:59models, but we don't really know,
0:30:59 > 0:31:05and that's why we have to send this up there, because if we don't, we'll never know.
0:31:05 > 0:31:12The latest infrared telescopes are ushering in a golden era in astronomy.
0:31:15 > 0:31:20These observatories have already started to rewrite the story of the universe.
0:31:23 > 0:31:26But despite their technical ability,
0:31:26 > 0:31:31they will only ever contribute a single chapter, not the whole book.
0:31:31 > 0:31:36To do this, requires telescopes that can capture other types of light,
0:31:36 > 0:31:40and examine the clues that this light contains.
0:31:42 > 0:31:46Back in the Atacama Desert, the quest for different forms of light
0:31:46 > 0:31:49is driving one of the most ambitious science projects on Earth.
0:32:03 > 0:32:07I think there's the potential to get a whole new window on the universe,
0:32:07 > 0:32:11to get a way to see into the biggest mysteries and to start to probe
0:32:11 > 0:32:14the ultimate origins of the universe.
0:32:16 > 0:32:19The questions are as big as they come.
0:32:23 > 0:32:27But the answers lie in the most inaccessible
0:32:27 > 0:32:29and invisible parts of space.
0:32:29 > 0:32:33Some of the biggest mysteries are the cold and dark places in space.
0:32:35 > 0:32:38If you look right back to as close as we can see to the Big Bang,
0:32:38 > 0:32:41those are the regions where the first galaxies are forming.
0:32:41 > 0:32:44But it's very hard to see those regions
0:32:44 > 0:32:48because of the gas and dust that they're actually forming from.
0:32:53 > 0:32:57Very little light can escape these frozen dust clouds.
0:32:57 > 0:33:00Yet some does make it through.
0:33:00 > 0:33:05It is known as submillimetre radiation.
0:33:06 > 0:33:09The problem for astronomers is that this form of light
0:33:09 > 0:33:14has less energy than infrared, making it harder to spot.
0:33:14 > 0:33:19To stand any chance, they need a radically different style of telescope.
0:33:19 > 0:33:23Well, it's very difficult to capture submillimetre light,
0:33:23 > 0:33:28because of the technology that's required, we need incredibly sensitive instruments to do it,
0:33:28 > 0:33:33you need a large telescope because the radiation is, is very, very weak
0:33:33 > 0:33:38and that radiation finds it very, very hard to get through the Earth's atmosphere,
0:33:38 > 0:33:41and so we go to the highest, driest places on Earth to do that,
0:33:41 > 0:33:46and it's one of those places that we're going to right now.
0:33:46 > 0:33:50At 9,500 feet, on the side of a mountain
0:33:50 > 0:33:57in the centre of the driest desert on Earth, Lewis and his team have built a telescope factory.
0:34:00 > 0:34:05Here, they are manufacturing large quantities of giant antennas...
0:34:05 > 0:34:09a necessity for capturing enough of the faint submillimetre light.
0:34:16 > 0:34:23What's so special is the way that all these antennas will be used together.
0:34:23 > 0:34:26But that won't happen here.
0:34:27 > 0:34:31They now need to be moved.
0:34:36 > 0:34:39This is, you might say, a pick-up truck or a jeep
0:34:39 > 0:34:42is a 4x4 vehicle. This is a 28x28 vehicle.
0:34:44 > 0:34:46It's 8am on a Monday.
0:34:46 > 0:34:49The start of a busy week.
0:34:49 > 0:34:50The science doesn't happen here.
0:34:50 > 0:34:54Although we've got something like 20 antennas around us at the moment,
0:34:54 > 0:34:56this isn't really where the observatory is.
0:34:56 > 0:35:01The antennas themselves, in order to do astronomy, get taken 25km from here,
0:35:01 > 0:35:05nearly two kilometres higher up than we are at the moment,
0:35:05 > 0:35:08which gives us a fantastic view on the universe.
0:35:08 > 0:35:13So we're taking it to the Chajnantor Plateau, which is very close
0:35:13 > 0:35:17to the triple border point between Chile, Argentina and Bolivia.
0:35:17 > 0:35:21The elevation is about 5,000 metres.
0:35:21 > 0:35:23The air density's about 50% that of sea level,
0:35:23 > 0:35:25so we're taking it to a place where
0:35:25 > 0:35:29there's basically very good astronomical observatory conditions.
0:35:45 > 0:35:50It will take three hours for the transporter to cover the 15 miles
0:35:50 > 0:35:55up to the 16,500 ft high plateau.
0:35:59 > 0:36:04For every foot gained in altitude, air density and temperature fall.
0:36:09 > 0:36:12This is extreme astronomy.
0:36:19 > 0:36:26Having now ascended 3,600 feet, the team are approaching a danger zone.
0:36:26 > 0:36:29It's time to check their oxygen levels.
0:36:29 > 0:36:34OK, we're on the way to the high site now, up at around about 4,000m,
0:36:34 > 0:36:37and because of the altitude, my blood oxygen level will be dropping,
0:36:37 > 0:36:40so I'm just going to stop and check
0:36:40 > 0:36:46how that's going, I know it was about 95% saturation when we started off at the 3,000m site.
0:36:46 > 0:36:51So it's actually pretty good now, it's at about 90, my pulse rate
0:36:51 > 0:36:55is up a bit, but oxygen level at 90 is very good.
0:36:55 > 0:37:01We try and always make sure that it stays above 80 as absolute minimum.
0:37:03 > 0:37:06Mistakes made here could be fatal.
0:37:06 > 0:37:12It can be very dangerous if your oxygen levels drop too low.
0:37:12 > 0:37:19The biggest issue for us for the project is your ability to think clearly drops off.
0:37:19 > 0:37:26People can have acute problems, so certainly people do die of severe altitude sickness.
0:37:29 > 0:37:33By midday, the team reach the plateau.
0:37:33 > 0:37:37It's the perfect location for gathering submillimetre light.
0:37:41 > 0:37:48The antennas here have over three miles less air to look through than if they were at sea-level.
0:37:48 > 0:37:53But at this extreme altitude, oxygen is an immediate concern.
0:37:53 > 0:37:59We've arrived at the high site now, we're on the Chajnantor Plateau, an altitude of 5,000 metres.
0:37:59 > 0:38:03The oxygen levels here are around about half what they are at sea level,
0:38:03 > 0:38:07so I can feel the difference now, it's pretty cold outside
0:38:07 > 0:38:09but I can also feel that my oxygen levels are dropping.
0:38:15 > 0:38:17Whoa!
0:38:17 > 0:38:21It's freezing up here now!
0:38:21 > 0:38:26I think the temperature's probably close to zero.
0:38:26 > 0:38:28And there's a pretty strong westerly wind blowing.
0:38:28 > 0:38:31So with the wind chill, that takes it well below zero.
0:38:34 > 0:38:39My oxygen levels have been dropping down into the 70s, which is really not high enough.
0:38:42 > 0:38:45Open the oxygen bottle, turn the flow rate down.
0:38:47 > 0:38:49It'll help me to concentrate,
0:38:49 > 0:38:53and help me think, and make me feel a bit better than I do just now,
0:38:53 > 0:38:55then get the cannula in.
0:38:57 > 0:39:01Not the best fashion accessory you've ever seen, but it works.
0:39:01 > 0:39:05The whole team are now on oxygen.
0:39:07 > 0:39:10Without it, operations of this complexity wouldn't be possible.
0:39:13 > 0:39:19Placing the antenna on the pad is an intricate task requiring full concentration.
0:39:19 > 0:39:23Those pads have precision ridges on them, three ridges,
0:39:23 > 0:39:27and they'll lower the antenna onto those ridges, being very careful
0:39:27 > 0:39:29about the positioning of the antenna.
0:39:29 > 0:39:33The combination of the skill of the operator and precision of those ridges means
0:39:33 > 0:39:38that we can locate this antenna to within around about a millimetre of a known position.
0:39:40 > 0:39:43Precision is vital.
0:39:43 > 0:39:48Each antenna is just a small part of a giant array, known as ALMA.
0:39:48 > 0:39:53When it's finished, 66 dishes will operate as one -
0:39:53 > 0:39:58the equivalent of an antenna ten miles across.
0:39:58 > 0:40:03A vast area is needed to capture enough submillimetre light.
0:40:03 > 0:40:07To enhance observations, the array can be reconfigured
0:40:07 > 0:40:11by relocating individual antennas.
0:40:11 > 0:40:14The effect will be like a camera zoom lens.
0:40:14 > 0:40:19When we have the antennas spaced very close tougher, that gives us the ability to see large structures
0:40:19 > 0:40:24in the sky. We can then move those antennas further out
0:40:24 > 0:40:29onto different pads, and make a larger single telescope
0:40:29 > 0:40:31comprised of those individual antennas,
0:40:31 > 0:40:34and that gives us the ability to see finer and finer detail.
0:40:35 > 0:40:38The complexity and scale of ALMA
0:40:38 > 0:40:42is a measure of the soaring ambitions of 21st-century astronomy.
0:40:45 > 0:40:47Never in human history
0:40:47 > 0:40:52have we been able to see so far out into the universe with such accuracy.
0:40:52 > 0:40:56I think there is something very special about what we get to observe
0:40:56 > 0:40:58with these sorts of instruments.
0:40:58 > 0:41:02They don't always produce pictures in the way that we think of the sky,
0:41:02 > 0:41:06but they produce amazing insights into what's really out there
0:41:06 > 0:41:10and they help us understand, not only how the universe
0:41:10 > 0:41:16is created, but they also do really, I think, satisfy our sense of wonder about our place in that universe.
0:41:24 > 0:41:28I'd really hope that in a few years' time, once ALMA's been in operation for a while,
0:41:28 > 0:41:31that it will have started to reveal the key science
0:41:31 > 0:41:35that we built it for, but I also am completely convinced
0:41:35 > 0:41:40that what ALMA will do, like all great observatories, is that it will detect things
0:41:40 > 0:41:42we haven't even predicted we'll be looking for.
0:41:42 > 0:41:47It'll be those complete unknowns, I think, that'll revolutionise our understanding of the universe.
0:41:50 > 0:41:54But despite the wonder they reveal, even the most advanced telescopes
0:41:54 > 0:42:00like this can only provide a partial picture of space.
0:42:00 > 0:42:05Astronomy now is becoming what we call a panchromatic science, really,
0:42:05 > 0:42:08you have to combine the information from different wavelengths,
0:42:08 > 0:42:11from different types of technologies and different observatories.
0:42:11 > 0:42:14And that's really where the great advances of astronomy
0:42:14 > 0:42:18and our understanding of the universe are going to come from.
0:42:18 > 0:42:23Now, the very first panchromatic view of the Universe is coming together,
0:42:23 > 0:42:30a breakthrough driven by the 21st-century renaissance in telescope construction.
0:42:32 > 0:42:37This is our nearest galactic neighbour, Centaurus A,
0:42:37 > 0:42:39seen in visible light.
0:42:39 > 0:42:42It's a striking image, but an incomplete one.
0:42:44 > 0:42:49When seen in the infrared, dust clouds begin to emerge.
0:42:49 > 0:42:53In ultraviolet light, it's clear that these clouds are the nurseries
0:42:53 > 0:42:58for thousands of bright young stars, all rotating around a central point.
0:43:00 > 0:43:04But to understand this requires X-ray imaging,
0:43:04 > 0:43:08which shows high-energy jets coming from the centre of the galaxy,
0:43:08 > 0:43:12the location of a supermassive black hole.
0:43:12 > 0:43:16But even here, the picture isn't complete.
0:43:16 > 0:43:22This radio image shows how the jets energise particles deep in space,
0:43:22 > 0:43:28creating vast radio pulses stretching out over millions of light years.
0:43:28 > 0:43:33The invisible has been made visible by a combination of telescopes
0:43:33 > 0:43:36working across the vast spectrum of light.
0:43:39 > 0:43:43But to fully understand the universe takes more than this -
0:43:43 > 0:43:48it requires a fundamental shift in what telescopes actually look for.
0:44:17 > 0:44:20Most people think that astronomy is about collecting light,
0:44:20 > 0:44:24but actually it's a lot more than that.
0:44:26 > 0:44:28Millard County, Utah.
0:44:31 > 0:44:33I think we are getting into an age
0:44:33 > 0:44:38where the old astronomical observatories, the classical ones
0:44:38 > 0:44:43that we're all familiar with, with optical telescopes - although they'll continue on,
0:44:43 > 0:44:49will gradually simply become part of a much larger set of instruments.
0:44:53 > 0:44:56Astronomers have always been collecting light,
0:44:56 > 0:45:00they're making bigger mirrors to look further into the universe.
0:45:00 > 0:45:02But there's another way to go, and that is to look at
0:45:02 > 0:45:08other kinds of energy that the universe is producing.
0:45:19 > 0:45:25Here, Professor Pierre Sokolsky has built a new kind of observatory.
0:45:26 > 0:45:31It's designed not to look for light, but subatomic particles.
0:45:35 > 0:45:38So here we are in the middle of this desert
0:45:38 > 0:45:42full of mosquitoes, and we're approaching what appears to be
0:45:42 > 0:45:48a rusty hospital bed, really kind of a piece of junk if you look at it,
0:45:48 > 0:45:52and yet it's part of a multimillion dollar experiment
0:45:52 > 0:45:55that consumes the passions of hundreds of scientists.
0:45:57 > 0:46:01It might not look like it, but this is a telescope.
0:46:04 > 0:46:06Part of one, at least.
0:46:14 > 0:46:18So we have an array of these detectors, they're about 500,
0:46:18 > 0:46:22507 of them exactly, they're spaced by about 1.2km,
0:46:22 > 0:46:27and it's a rectangular array which covers this whole basin.
0:46:27 > 0:46:31The detectors lie in wait for an elusive particle
0:46:31 > 0:46:36first seen by astronauts on their historic first mission to the Moon.
0:46:36 > 0:46:39'Tranquillity Base, Houston.
0:46:39 > 0:46:42'Roger, go ahead. You're cleared for take off.
0:46:42 > 0:46:45'Roger, understand. We're number one on the runway.'
0:46:45 > 0:46:4721st July, 1969.
0:46:51 > 0:46:55Neil Armstrong and Buzz Aldrin blast off from the Moon.
0:46:55 > 0:47:00They now face a long and perilous journey back home.
0:47:00 > 0:47:02'Roger, we got you coming home...'
0:47:04 > 0:47:08Only 24 men in history have been this far from Earth.
0:47:08 > 0:47:14Nearly all of them reported what Armstrong and Aldrin saw next.
0:47:14 > 0:47:19Here, beyond Earth's protective magnetic field,
0:47:19 > 0:47:22the astronauts started seeing stars.
0:47:23 > 0:47:26Even with their eyes shut.
0:47:28 > 0:47:31Bizarre dots and flashes of light rippled through their vision.
0:47:31 > 0:47:36Only later did scientists work out that these phenomena
0:47:36 > 0:47:40were probably caused by particles called cosmic rays
0:47:40 > 0:47:45passing through the vitreous humour, the gel between the lens and retina
0:47:45 > 0:47:46in the astronauts' eyes.
0:47:48 > 0:47:51One of the marvellous things about cosmic rays
0:47:51 > 0:47:53is that they're really messengers -
0:47:53 > 0:47:57they're actually pieces of matter from distant galaxies,
0:47:57 > 0:48:02so they're a marvellous gift to us to study.
0:48:05 > 0:48:10These intergalactic messengers are constantly bombarding our entire planet.
0:48:13 > 0:48:18But to this day, an essential mystery remains unsolved -
0:48:18 > 0:48:22nobody knows which objects in the universe produce cosmic rays.
0:48:22 > 0:48:28To find out, astronomers here aren't trying to catch one directly -
0:48:28 > 0:48:30they're trying to spot its effects.
0:48:30 > 0:48:35So when a cosmic ray hits the atmosphere, it produces what's called an air shower.
0:48:37 > 0:48:42That's a bundle of billions of particles that travel very near the speed of light,
0:48:42 > 0:48:47across the atmosphere and hit the ground, and this is actually what these detectors detect.
0:48:47 > 0:48:51Under the metal cover is a plastic layer...
0:48:51 > 0:48:55the equivalent of the vitreous humour in the astronauts' eyes.
0:48:55 > 0:48:59It absorbs then releases energy from the air shower
0:48:59 > 0:49:01as a detectable flash of light.
0:49:01 > 0:49:05But it's one thing to observe the arrival of a cosmic ray,
0:49:05 > 0:49:08quite another to pinpoint its origin.
0:49:08 > 0:49:11It's very difficult to track down the origin of cosmic rays
0:49:11 > 0:49:14just with this equipment, and the reason is
0:49:14 > 0:49:19that we're looking at the very tail end of this shower of particles
0:49:19 > 0:49:21produced by the cosmic ray.
0:49:21 > 0:49:26So it's a bit like describing an elephant by looking at its tail,
0:49:26 > 0:49:29you really have to see the whole object, and to see the whole object,
0:49:29 > 0:49:31we need to look high in the atmosphere
0:49:31 > 0:49:36and see what's happening as that cosmic ray travels through the atmosphere.
0:49:45 > 0:49:50To achieve this, Professor Sokolsky is relying on another type of detector.
0:49:52 > 0:49:56This is an air fluorescence telescope.
0:49:56 > 0:50:00It captures the flicker of ultraviolet light
0:50:00 > 0:50:04which is produced as cosmic rays travel through the atmosphere.
0:50:06 > 0:50:11So we have three such detectors, one here, one twenty kilometres
0:50:11 > 0:50:15in this direction, one twenty kilometres in this direction.
0:50:15 > 0:50:21So by triangulating the position of this cosmic ray, we can then figure out what angle it came from
0:50:21 > 0:50:24and extrapolate that direction back onto the sky, to see -
0:50:24 > 0:50:28is there an object that it came from?
0:50:30 > 0:50:33The current theory is that cosmic rays
0:50:33 > 0:50:38come from jets streaming from the region around supermassive black holes.
0:50:38 > 0:50:45When you're looking at that, at those edges, at those frontiers, you very often discover
0:50:45 > 0:50:48the inadequacies of your understanding,
0:50:48 > 0:50:52and in that process learn something new about the laws of nature.
0:50:52 > 0:50:58So, revolutions occur very often in step with revolutions in technology,
0:50:58 > 0:51:01revolutions in scientific thought.
0:51:01 > 0:51:04Since Galileo first turned his telescope
0:51:04 > 0:51:07to the heavens four centuries ago,
0:51:07 > 0:51:10new technology has driven our understanding of the cosmos.
0:51:10 > 0:51:13It's a tradition that continues today,
0:51:13 > 0:51:16even in the most unlikely locations.
0:51:19 > 0:51:25The world of telescopes doesn't get much stranger than this.
0:51:31 > 0:51:36Here in France, astronomers are beginning to redefine what a telescope actually is.
0:51:52 > 0:51:58Dr Paschal Coyle is sailing for one of the most unusual telescopes in existence.
0:52:00 > 0:52:04We're just now leaving the port of Toulon in the South of France,
0:52:04 > 0:52:09the telescope is located 40 kilometres off shore.
0:52:14 > 0:52:17The Pourqois Pas is heading for ANTARES, a telescope designed
0:52:17 > 0:52:22to spot the most elusive and mysterious cosmic particles of all -
0:52:22 > 0:52:24neutrinos.
0:52:26 > 0:52:31Neutrinos are a bizarre elementary particle,
0:52:31 > 0:52:35they have no charge, they essentially have very little mass,
0:52:35 > 0:52:39so they interact very little with matter.
0:52:39 > 0:52:44So we have to build telescopes which are enormous to have even
0:52:44 > 0:52:47the smallest chance to detect just a handful of neutrinos.
0:52:51 > 0:52:54Detecting a virtually invisible particle is a real challenge.
0:52:54 > 0:52:59But if the team's telescope can spot one, and work out where it came from,
0:52:59 > 0:53:03they might rewrite the rules of the universe.
0:53:03 > 0:53:07So the boat has now reached the site of the telescope,
0:53:07 > 0:53:11and it's located 2.5km below the boat.
0:53:15 > 0:53:19Everybody is preparing the submarine to be deployed.
0:53:21 > 0:53:25A telescope on the bottom of the ocean might sound strange,
0:53:25 > 0:53:27but that's only the start.
0:53:29 > 0:53:34Because the telescope this remotely-operated submarine is heading for
0:53:34 > 0:53:37doesn't look up into the Mediterranean skies,
0:53:37 > 0:53:41but down through the planet.
0:53:42 > 0:53:47It's all due to the incredible properties of the neutrinos themselves.
0:53:49 > 0:53:56Somewhere far out in the universe, we expect there are sources of very high-energy neutrinos.
0:53:56 > 0:54:00The distances are enormous, they can be millions and billions of light years away.
0:54:00 > 0:54:07If we're lucky, some of these neutrinos will come close to the Earth, and pass through
0:54:07 > 0:54:14the atmosphere, in Australia, pass right through the centre of the Earth, through the core of the Earth
0:54:14 > 0:54:17without really even noticing it's there.
0:54:17 > 0:54:21Having passed through the entire planet, the neutrino will bump
0:54:21 > 0:54:24into an atom of seawater, causing a flash of light.
0:54:26 > 0:54:31The telescope, strings of light-sensitive detectors suspended in the ocean,
0:54:31 > 0:54:33will spot this light.
0:54:33 > 0:54:36Or so the astronomers hope.
0:54:37 > 0:54:41The name of the game with neutrino telescopes is to essentially make
0:54:41 > 0:54:44a neutrino sky map of the universe.
0:54:46 > 0:54:54This search for the slippery cosmic neutrino represents a significant scientific challenge.
0:54:56 > 0:55:00Their slipperyness is what makes them so valuable.
0:55:00 > 0:55:05They pass through cosmic obstacles, revealing the hidden universe beyond.
0:55:05 > 0:55:11Observing one requires not only immense scientific and engineering prowess,
0:55:11 > 0:55:14but also a large helping of luck.
0:55:16 > 0:55:20And today, luck is in short supply.
0:55:20 > 0:55:25A cable connector here on the telescope on the seabed is jammed.
0:55:25 > 0:55:30Normally a broken connector isn't such a major problem.
0:55:30 > 0:55:37When it happens 2.5km under the sea, it's almost a disaster.
0:55:40 > 0:55:44It's a long night for the team in the control room.
0:55:44 > 0:55:48But despite their best efforts, the connector remains jammed.
0:55:49 > 0:55:52Another mission will be needed.
0:55:53 > 0:55:57Beneath the waves, the telescope is still operational.
0:55:59 > 0:56:06But in over three years of searching, the neutrino hunters haven't found a single cosmic neutrino.
0:56:09 > 0:56:14Yet their enthusiasm and optimism remains undimmed.
0:56:14 > 0:56:20We are convinced that these elusive neutrinos are there, we don't really know how big a detector
0:56:20 > 0:56:26we actually need to be able to find them, so maybe it'll happen that we
0:56:26 > 0:56:30won't find any, in that case we will try to build a bigger ANTARES,
0:56:30 > 0:56:37so we have plans to build a new detector which will be 50 times bigger than Antares.
0:56:40 > 0:56:43This is the story of how great discoveries happen.
0:56:45 > 0:56:49Nobody really knows what the team might end up discovering.
0:56:49 > 0:56:56History has shown that every time we look at the universe in a new way,
0:56:56 > 0:57:01we have had expectations of what we might see, but in fact
0:57:01 > 0:57:05the most interesting things were the things we didn't expect.
0:57:07 > 0:57:12This is the true power of telescopes.
0:57:12 > 0:57:17Many no longer look like telescopes,
0:57:17 > 0:57:21but their ability to change our view of the universe places them
0:57:21 > 0:57:25among the most intellectually explosive instruments ever made.
0:57:27 > 0:57:31The 21st-century renaissance in telescope construction
0:57:31 > 0:57:35will answer the greatest questions in cosmology,
0:57:35 > 0:57:37and pose new ones.
0:57:37 > 0:57:42It's very exciting to be an astronomer right now.
0:57:42 > 0:57:46We have telescopes in space, we have telescopes at mountaintops,
0:57:46 > 0:57:48we have telescopes in airplanes.
0:57:49 > 0:57:55I certainly can't imagine a time when we would be done asking questions.
0:57:55 > 0:58:00I can't imagine that as human beings we'd ever be there.
0:58:00 > 0:58:03I know sometimes people feel insignificant or small
0:58:03 > 0:58:07when they think about astronomy, and they think about the cosmos.
0:58:07 > 0:58:10And I think it's amazing that we are the people,
0:58:10 > 0:58:14we are the species who are able to understand how we got here.
0:58:14 > 0:58:18And that's not small, that's pretty amazing.
0:58:52 > 0:58:55Subtitles by Red Bee Media Ltd
0:58:55 > 0:58:58E-mail subtitling@bbc.co.uk