"Every day, in every town, there's a moment when, for the first time, we stare into the eyes of Mum and Dad and are welcomed into the arms of the universe." "# Open up your eyes Then you realise" "# Here I stand with my Everlasting love... #" "Every human life has to start somewhere, a place in space and time, and I started here, on March the 3rd, 1968, in the Royal Oldham Hospital." "In 1971 we moved here to the family home in Chadderton - it's only about a mile away from the hospital." "I stayed here for the next 18 years." "In 1979 my world expanded a bit cos I came up the hill to this school, Hulme Grammar School." "This was my form room, 3Y, and that was the end of the universe because the girls' school was through there." "And it wasn't long before I began to wonder how my world fitted into the wider cosmos." "My grandad used to tell me how he walked up onto this hill in the summer of 1927 to see a total solar eclipse." "And because of that story, I always wanted to see one, and I finally got to do it 80 years later." "And it was a very powerful experience." "I didn't know what I'd think." "He always spoke of the sky going dark and everything going quiet and the birds stopping singing." "What I felt was that I was on a ball of rock." "I had a very powerful sense that I was on this... this rocky planet, orbiting in the blackness of space around a star." "That understanding of where we are is the culmination of a 400-year journey of scientific discovery." "This is the story of how we are measuring with increasing precision our place in space and time." "How we've discovered that we are an infinitesimal speck in a possibly infinite universe, and, in doing so, just how valuable we are." "As far as we know, we humans are unique in the universe." "The only creatures that have developed the ability to ask deep questions about the cosmos." "This curiosity has led us to a profound change in perspective." "From believing we were the most important creatures in all creation we have uncovered humanity's true place in the cosmos and glimpsed our earliest origins." "This is the fortified town of Ait Benhaddou." "It was built in the 17th century on the trade route that winds its way north across the High Atlas and into the markets of Marrakech." "The indigenous Berber people who built this place have been in this part of North Africa for well over 10,000 years, and they're mentioned in Ancient Egyptian texts and in Greek - both Herodotus and Cicero talk of these people who worship the sun and the moon." "In fact, they tell a story of how they cut off the ears of goats, threw them over their houses in honour of the moon god, Ayyur." "And the skies are so crystal clear here that you can see why they did it." "Well, not the goat thing, but worshipped those celestial objects in the sky." "High above the village, the summit affords an unobstructed view of the heavens." "The perfect vantage point from which to ponder your place in the universe." "For all of history, or at least, I imagine for as long as people have considered such things, the Earth has been thought of as being motionless, at the centre of the universe." "And when you think about it, that's obvious - it doesn't feel like we're moving, and the ground feels solid beneath our feet, the proverbial mountains move for no-one, and the sun, moon and stars arc across the sky." "The Earth is motionless at the centre, and the universe rotates around it." "Watching the night sky, it's natural to think that the stars move around us." "And so, for thousands of years, this geocentric view of the universe was never questioned." "And it's not just the motion of the stars " "Aristotle and the ancient Greek philosophers thought about these things in detail." "They noticed that when you drop things they always fall towards the centre of the Earth, so therefore there must be something special about the Earth, it must be the centre of the universe." "These arguments are so persuasive that it was millennia before they were overturned." "It was here in Venice that our demotion from the centre of the universe began." "Venice was an independent city-state for well over 1,000 years, and by the 15th century it was the richest city in Europe." "You see that legacy everywhere - the buildings are spectacular, you can only imagine what it must have been like in its heyday." "And that pre-eminence put it at the centre of arguably the greatest intellectual revolution in the history of human civilisation - the Renaissance." "The Renaissance was a period when the rebirth of art and science transformed how we saw the world." "This is the Scuola Grande di San Rocco, and everywhere you look, there is masterpiece after masterpiece from one of the greatest artists of the Italian Renaissance, Tintoretto." "It took him over 20 years, beginning in the 1560s, to complete this building." "And it's breathtaking." "You see scenes from the Old Testament on the walls, scenes from the New Testament." "And what's striking, apart from the obvious skill of the painter, is the realism." "And there" " The Last Supper." "You could almost walk into that painting, you could walk across that chequered floor, up the stairs, turn right and out through that illuminated doorway." "In the art of the medieval period and before, you don't see this depiction of real space, the paintings are flat." "From the 14th century, with the rediscovery of the geometry of the Greeks, then you see a genuine intellectual shift, you see the desire to paint the world as it really is, you see paintings with perspective and depth." "And that was a change in perspective." "And we got our first hints of our planet's true place in the cosmos when this desire to see things as they are was combined with the city's most valuable commodity." "During the Renaissance, these craftsmen were so valuable to Venice that they were barred from leaving the city on pain of death." "Murano glass was so prized because its clarity allowed it to be fashioned into optics, into mirrors and lenses." "And it was precisely that property that caught the eye of one of the period's most renowned figures," "Galileo Galilei." "Now, in 1609, Galileo came here to Venice to commission lenses for his new telescope - this was the world centre of glass production - and he immediately put that telescope to good use by turning it towards the moon and sketching what he saw." "In the 1600s, most people thought that anything in the heavens was perfect, perfectly round, perfectly smooth, but Galileo depicted the lunar surface as we know it to be today, the sunlight bouncing off mountains, disappearing into valleys," "its shaded rims of craters." "Galileo didn't just observe the moon with his telescope, he turned it to the planets and also in 1610 he made this series of sketches of Venus and he noticed that, different times of the year, Venus can appear as a full circle" "in the sky or as a slim crescent and as everything in-between." "When Venus is on the other side of the sun from the Earth, we see the whole planet." "But as it moves around in its orbit, less and less sunlight is seen to strike its surface until it crosses the sun in silhouette." "The only credible explanation for these phases of Venus is that Venus is a planet, it's orbiting the sun inside the orbit of the Earth, which is also orbiting the sun." "So, this is the first confirmation of a sun-centred solar system." "Galileo had seen evidence that the sun, not the Earth, was the centre of the solar system and began our scientific exploration of the universe in earnest." "In the last 50 years, we've done more than simply look out from Earth, we've sent unmanned spacecraft to every corner of the solar system...'" "No, no, no!" "Tram!" "..Many not much bigger and not much more advanced than this car.'" "Oops, sorry." "It's a beautiful piece of engineering, but it's essentially got no brakes." "We sent Mariner 10 and Messenger to Mercury, the closest planet to the sun...'" "It's got no acceleration." "I don't know what these sticks do here." "2.43 missions to Venus..." "..and 51 to Mars.'" "Wa-hey!" "But only a handful have made it into the solar system's outermost reaches.'" "In 1977, a chance alignment of the planets meant that it was possible, at least in principle, to launch a spacecraft to all four of the outer gas giants." "So, NASA launched two spacecraft, Voyagers 1 and 2." "And just 18 months later, they reached the largest planet in the solar system, aptly named after the Roman king of the gods, Jupiter." "They explored Saturn before separating, with Voyager 2 going on to visit Uranus." "And then, in 1989, after travelling for 12 years it reached Neptune the most distant planet in the solar system." "But perhaps the most dramatic change in perspective came on the 21st of December 1968 when we left the Earth for ourselves and set out for another world." "When you're up flying on a beautiful day, you're certainly free, like a bird, and I just enjoy the scenery and the solitude of it." "I've probably got over 13,000 hours in the air." "But as a fighter pilot, one of the things I pride myself in is more landings than I have hours." "Of all the flights Major General Bill Anders has taken, he'll be remembered for the one he made when he was just 35." "In the 8th year of manned flight into space, the National Aeronautics and Space Administration prepared men and equipment for the most advanced manned mission to date." "Together with Frank Borman and Jim Lovell," "Bill climbed aboard the most powerful machine ever built by man." "When the rocket ignited, the giant 5F1 engines putting out a total of 7½ million pounds of thrust, the racket was unbelievable." "We have lift-off, lift-off at 7:51am Eastern Standard Time." "The sideways forces, as those rockets gimballed to try to keep us pointed straight up, threw us around in the spacecraft." "If we hadn't been strapped in, we'd be bouncing off the walls." "We flew out of the noise and echo from the Earth and we knew we were on our way." "This is Houston, you're looking good." "We hear you loud and clear, boys." "OK, the first stage was very smooth and this one is smoother." "The three astronauts had begun the longest human journey ever attempted." "I can see the entire Earth out of the centre window." "I can see Florida, Cuba, Central America." "Over 68 hours and 57 minutes, they travelled across 380,000 kilometres of empty space until suddenly their tiny craft was plunged into darkness." "The stars just exploded, I mean, there were..." "Every star you ever thought about was visible to the degree that it was very difficult to pick out constellations." "And yet, as I looked back over my shoulder, the stars suddenly stopped and it was this big, black hole and that was the moon." "And I must say, that got the hair on the back of my neck standing up a little bit." "On Christmas Eve, 1968, Apollo 8 entered lunar orbit." "It was just one crater on top of another crater and no matter how closely you looked, you're going to find smaller and smaller craters on top of the big ones." "It looked like a battlefield, it was totally beat up." "It was as they emerged from behind the desolate lunar surface for the third time that our perception of the Earth changed for ever." "When we finally turned around and were going forward, like a car driving on down the highway, we saw for the first time the Earth come up on the lunar horizon." "I set the range at infinity, pointed it at the Earth and just started clicking away, changing the F-stop with every click." "The photograph was the shotgun approach, figuring one of them was going to hit, and indeed it did." "The photograph Anders took is known as Earthrise." "One of THE iconic images of our time." "After the flight, I've often been asked what I thought was the most significant part of Apollo 8, its biggest contribution, and I've often said our mission really was to explore the moon, but our accomplishment was that we discovered the Earth." "It was only by looking back at our planet from afar that we felt just how small and delicate a part of the universe our fragile world really is." "When I look up and realise that the moon is a long way off, 240,000 miles, and sometimes it's hard to imagine that we actually zipped all the way up there and around it 11 times and back, in this day and age." "Hundreds of years of exploration have revealed our planet to be just one of eight in orbit around a star we call the sun." "But understanding our place in the solar system is only the first step in finding our place in the universe because far beyond anywhere we can visit lie the stars." "Until recently, there was no way of knowing how distant the stars are." "And so we had no idea of our star's true place in the heavens." "I've been roping since I was a little kid." "Now, the older I get, the more I like roping, it's a very important part of the cowboy lifestyle." "The most important skill when you're roping is accuracy and judging the distance." "You've got to be a real good judge of where the steer is going to be when you throw your rope." "Because our eyes are a few inches apart, each one captures a slightly different view of the world." "And comparing the differences between the two images is one of the ways the brain judges distance." "It's a phenomenon known as parallax." "And remarkably, you can use the same effect to measure the distance to the stars." "Now, the parallax shift of a star in the sky from one eye to the other is of course imperceptibly small, but if you could arrange for your head to be, let's say," "180 million miles in diameter, then the parallax shift would be measurable." "And you can do that." "Here are two pictures of a double-star system called 61 Cygni taken in May and November." "That's when the earth is on one side of the sun...and the other." "There is your 180 million miles." "And as you can see, the shift is small... but noticeable." "Using parallax, 61 Cygni was found to be 104,000 billion kilometres from earth." "But this technique only works for our nearest stellar neighbours." "The vast majority of stars are so much further away that they exhibit no perceptible parallax shift at all." "So to go beyond our local stellar neighbourhood, a new technique was required." "And it involved measuring the brightness of the stars themselves." "If you want to use the brightness of a star as seen from the earth's surface to measure its distance, then you have to know how bright the star actually is." "And the first person to work out how to do that was one of the great unsung heroes in the history of astronomy" " Henrietta Leavitt." "Leavitt was cataloguing the brightness of stars from photographs and she became interested in a particular kind of star known as a variable star, which changes its brightness over time." "So it goes dimmer and brighter, dimmer and brighter, over a period of days or weeks or even months." "She took a special interest in a class of variable stars called Cepheids." "Now, what Leavitt noticed was that there is a simple relationship between the actual brightness of a Cepheid variable and the rate of change of that brightness - its period." "She noticed that, for the dimmer Cepheid variables, the rate of change of brightness is very fast, whereas for the brightest of the Cepheids, the rate of change is slow." "So that means that if you can determine the distance to just one Cepheid variable by parallax, then you know the distance to all of them just by measuring the rate of change of the brightness in the sky." "Within a year of the publication of the paper in 1912, the size of the Milky Way galaxy had been measured and shown to be 100,000 light years across, with the sun not near the centre, but close to the edge." "The Milky Way is a disc of between 200 and 400 billion stars reaching out in giant spiral arms." "The sun and the solar system sit within the inner rim of the Orion arm," "27,000 light years from the galactic centre, which they orbit once every 240 million years." "But as vast as the Milky Way is, it wasn't long before we found Cepheid variables that were far more distant." "Our galaxy wasn't the only one." "Five, four, three two, one... and lift-off of the space shuttle Discovery with the Hubble Space Telescope, our window on the universe." "Only 400 years ago," "Galileo used simple glass lenses to explore the solar system." "Today we use advanced instruments like the Hubble Space Telescope to explore the universe." "Do you like this, Houston?" "Oh, it's not bad." "Hundreds of billions of galaxies stretching out in every direction to the edge of the observable universe some 46 billion light years away." "We've discovered that the universe is far grander, far more majestic than anyone suspected when we first started exploring it just a few centuries ago." "We've discovered there are no special places in the universe." "We are not at its centre, we just orbit around one of a trillion suns." "Which raises an obvious question - where did all those stars come from?" "For 51 weeks a year, the 88 households of Souad's tiny village make up her entire universe." "But this week will be different." "For a few days every year, thousands of Berber tribespeople from across the High Atlas leave their isolated villages to attend a festival of marriage in the hope of finding a partner and so beginning a new chapter in their family history." "Just as in Souad's family, for as long as anyone can remember, each generation of Berber have returned to this place to begin the next generation." "Today we can trace our origins much further back than our immediate family tree, back in fact further than the origin of our species here in Africa, back past the origin of life on earth and the formation of earth itself." "Back, in fact, to what appears to be the beginning of time." "And that didn't require a journey of exploration in a spaceship, flying off into the unknown." "It just required something that we all possess - the human imagination." "Scientists are often described as being childlike, and the archetypal example is Albert Einstein." "I think it means thinking with simplicity." "Following threads carefully and tenaciously, seeing where they lead." "Following the implications of a thought through, and asking the question why, why, why, why?" "It's having a mind uncluttered by the adult affliction of common sense." "Einstein would free his mind of the everyday and allow it to wander through the universe." "He imagined himself riding on a beam of light." "And, by wondering what he might see, transformed our understanding of space and time." "But it was his re-imagining of an experiment dreamt up by Galileo in the 1500s that laid the foundations of modern cosmology." "Einstein called it the happiest thought of my life." "Which is in itself an almost childlike sentence, because following that thought through ultimately led us to a theory of the origin of the universe itself." "And there's a place where you can see with your eyes what Einstein saw in his mind." "This is NASA's space power facility near Cleveland, Ohio, and it is the world's biggest vacuum chamber." "It's used to test spacecraft in the conditions of outer space and it does that by pumping out the 30 tonnes of air in this chamber until there are about two grams left." "It's kind of got an eccentric construction, which is part of its history." "It was built in the 1960s as a nuclear test facility to test nuclear propulsion systems, and that meant that they built it out of aluminium to make the radiation easier to deal with." "Aluminium is not the best thing, the strongest material, to build a vacuum chamber out of, so they built an outer concrete skin which is part radiation shielding and part an external pressure vessel so this thing can take the force that's present on the outside" "when it's pumped out to the conditions of outer space." "Galileo's experiment was simple - he took a heavy object and a light one and dropped them at the same time to see which fell fastest." "Now, in this case, the feathers fell to the ground at a slower rate than the bowling ball because of air resistance." "So in order to see the true nature of gravity, we have to remove the air." "It takes three hours to pump out the 800,000 cubic feet of air from the chamber." "OK, we dropped two millitorr in the last 30 minutes." "But once it's complete, there's a near-perfect vacuum inside." "...10% open, station one, go for drop." "PCB 30-1, pressure set point at 240 psi." "We are go for drop." "Ten, nine, eight, seven, six, five, four..." "Cameras on. .." "Two, one." "Release." "Exact." "Look at that." "They came down exactly the same." "Wow!" "Oh, look, look." "Look how they hit right there." "Holy mackerel!" "Exactly." "Exactly the same." "The feathers don't move, nothing." "Look at that, that's just brilliant!" "Isaac Newton would say that the ball and the feather fall because there's a force pulling them down - gravity." "But Einstein imagined the scene very differently." "The happiest thought of his life was this." "The reason the bowling ball and the feather fall together is because they're not falling." "They're standing still." "There is no force acting on them at all." "He reasoned that if you couldn't see the background, there'd be no way of knowing that the ball and the feathers were being accelerated towards the earth." "So he concluded...they weren't." "Instead, Einstein proposed that the force of gravity is an illusion." "Just as the surface of the earth isn't flat, neither, he said, was the fabric of space." "All objects, like stars and planets, warp the space and time around them to produce valleys." "And all objects, like planets and bowling balls, move across this curved landscape giving the appearance of being diverted by a force." "Einstein called this theory General Relativity." "Esoteric and strange as Einstein's theory of gravity seems, it can be tested." "The Arecibo Observatory in Puerto Rico has the largest dish of any telescope anywhere in the world enabling it to detect the faintest radio waves from galaxies far, far away." "When we come back, we should destroy the shield generator." "Using telescopes like this, we witness some of the most violent gravitational events in the cosmos." "The deaths of giant stars." "Entire suns devoured by black holes." "And here at Arecibo, they've studied one of the most extreme systems in the universe, a binary pulsar, and measured the stars' doomed orbits as they spiral towards each other to the last millimetre." "These measurements are so precise that using this telescope it's found that the radius of the orbits is decreasing by 1.7 millimetres a day." "That number is precisely the number calculated using Einstein's theory." "This is why I think that Einstein's theory of general relativity is arguably the greatest achievement of the human intellect." "It is, as far as we can tell, a precisely accurate description of everything we look at in the universe." "But Einstein soon realised his equations could do far more." "They could rewrite the most universal of human stories." ""In the beginning, God created the heaven and the earth..."" "..and the earth was without form and void and darkness was upon the face of the deep."" "And the spirit of God moved upon the face of the water and God said, Let there be light'..."" "..and there was light." "Einstein's equations allow you to predict the shape of space-time given the distribution of matter within it." "So if you plug a spherical blob of matter into his equations - the sun, let's say - then Einstein's equations give you a solar system." "They allow you to understand its past and to predict its future." "And shortly after Einstein published the theory, he had another happy thought." "He thought, well, if you can do that for a solar system, why can't you do it for a universe?" "Think about that for a minute - understand the past and predict the future of the entire universe." "Even Einstein thought he'd gone too far." "Because to do that, you need to know how matter is distributed not just around a single star, but across the whole cosmos." "The simplest thing you can do is to assume that the universe is the same everywhere, there are no special places." "You assume a completely uniform matter distribution." "And when you do that, then Einstein's equations predict something surprising." "They predict that the universe can't be static, that the universe is dynamic, it's constantly changing." "Now, if you have an expanding universe, then that implies that it was smaller in the past, and ultimately, it implies that there was a beginning." "The Belgium priest and mathematician Georges Lemaitre, who was one of the first to work on these solutions, put it beautifully." "He said, "The universe must have had a day without a yesterday."" "Einstein's equations describe the evolution of the universe all the way back to its very first moments." "From its adulthood, with mature stars and galaxies through adolescence to its childhood and the formation of the first stars." "With every step back in time, the fabric of space contracts and the universe gets smaller." "Until 13.8 billion years ago, it was born... in the big bang." "And perhaps the ultimate triumph of our exploration of the cosmos is that in the last few years we've taken a snapshot of the universe in its infancy." "Dix, neuf, huit, sept, six, cinq, quatre, trois, deux, un..." "Go!" "On 14th May 2009, the Planck Satellite was launched from ESA's spaceport in French Guiana." "Its mission was to travel one and a half million kilometres into deep space and there, far from any interference from earth, to witness the birth of the cosmos." "For four years, Planck scoured the heavens, gathering the oldest light in the universe - light that began its journey to earth long before there were any humans to witness it." "Light that is older than any galaxy, more ancient than any star." "The cosmic microwave background." "This is the photograph of that light that was released 380,000 years after the big bang and has been journeying through the cosmos ever since, for almost the entire history of the universe." "It really is the afterglow of the big bang." "In those first moments, the universe was a fireball of hot, opaque plasma." "But as it cooled, the first atoms formed and the first light was free to roam through the universe." "And encoded in minute temperature differences in that light, is the story of our earliest origins." "Those tiny variations in the temperature of this radiation which correspond to tiny fluctuations in density in the universe when it was only 380,000 years old are vitally important, because these are the seeds of the galaxies." "Without these slight density variations, there would have been nothing for matter to coalesce around and we wouldn't exist." "And that makes this, I think, by far the most remarkable picture of all time." "So this is our place in space and time - 13.8 billion years from the big bang 27,000 light years from the centre of the Milky Way galaxy on a rocky world orbiting a yellow main sequence star." "Today, the 21st of June, the earth's northern hemisphere is tilted towards the sun and here in Poland, people gather to celebrate the shortest night of the year." "We've come a long way." "In only 500 years, we've journeyed to the edge of our solar system and photographed our home world." "We've counted the galaxies, we've captured the most ancient light in the universe and measured its age, and in doing so, we've discovered that we are just one planet in orbit around one star amongst billions," "inside one galaxy amongst trillions, afloat in a possibly infinite sea of space-time." "In finding our place in the universe, we've come to realise how small and fragile a part of it we are." "But it's been the most glorious ascent into insignificance, because our physical demotion has been the inevitable consequence of a daring intellectual climb from being the puppets of the gods to that most rare and precious thing, a scientific civilisation." "The only one we know of anywhere in the universe that's been able to comprehend its true place in nature." "And that is our greatest achievement."