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1  The Demonic Ape

In a film that is in turns charming, disturbing and poignant, Horizon explores the relationship between science and the chimpanzee. It began with a magical story. A young girl ventured alone into the jungle and befriended a group of chimpanzees. What she saw became the stuff of scientific legend. But then, last year came a terrible tragedy. Frodo, one of the chimpanzees she had helped make famous, killed a human baby. That shocking act brought into focus a huge debate about the relationship between humans and chimps, and what these primates have taught us about the origins of our own behaviour. The saga of how Jane Goodall went into the jungle to study the chimps of Gombe in Tanzania has inspired novels and movies. Her observations revealed that chimpanzees were in many ways like humans. They used tools, had culture and even language. And what's more they had empathy. They were also capable of savage brutality against their own kind. Just like us. In fact many began to think that the origins of aggressive human male behaviour could be traced back to our shared evolutionary ancestry with chimps. In other words, men are genetically programmed to be violent. But then came some disturbing questions.

Air Date: 2004-01-08

2  The Moscow Theatre Siege

With the help of doctors and scientists in America, Germany and Britain, Horizon unpicks the mystery of the Moscow theatre siege. In October 2002, Chechen terrorists took a thousand people hostage in a Moscow theatre and threatened to kill them. The problem was how to get them out alive. A bloodbath seemed inevitable. Three days later Russian special forces stormed the theatre using a secret gas to knock everybody out. 129 hostages died - apparently killed by the very gas that was meant to save them. Horizon investigates the mystery substance, and why so many died. The Russian authorities insisted their secret weapon was not lethal. The claim provoked contempt from the victims families, and incredulity among doctors and scientists around the world. But were the Russians actually right? The Russians offered just one clue. And in Germany there was a scientist who had the means to test it: a urine sample taken from one of the survivors shortly after he was freed. Horizon follows as extremely sensitive tests are performed to find out if the Russians were telling the truth, and uncovers a deeper secret.

Air Date: 2004-01-15

3  The Atkins Diet

This is the truth about the world's most famous, most glamorous and most controversial diet. The Atkins diet says that eating fat can make you thin. It says you don't need to bother watching the calories. Rene Zellweger, Geri Halliwell and a host of other celebrities swear by it. But many scientists think it is scientific nonsense. Some even believe it is dangerous. Horizon cuts through the confusion and provide the answers. When Dr Atkins first launched his diet, he was accused of breaking one of the most fundamental laws of nature. Scientists said that if you eat more, you'll get fatter. They also said it could kill. Fat increases your cholesterol levels. You'd get a heart attack. The only problem was that people who followed the Atkins diet got thinner. Much of the rest of us got fatter. Then came studies showing that cholesterol levels can actually improve on the Atkins diet. So what was going on? Horizon's investigation seems to show that the diet may really work - but for a reason and in a way that no scientists or even Atkins himself had seriously considered.

Air Date: 2004-01-22

4  Secrets of the Star Disc

This is the extraordinary story of how a small metal disc is rewriting the epic saga of how civilisation first came to Europe, 3600 years ago. When grave robbers ransacked a Bronze Age tomb in Germany, they had no idea that they had unearthed the find of a lifetime. But they knew that it was worth selling. It was a small bronze disc of exquisite design. So they contacted the archaeologist Harald Meller, offering to sell it to him for €300,000. Meller went deep into the criminal underworld and, after a police sting, he got his disc. It depicted the sun, the moon and the stars. This suggested an understanding of the heavens greater than that of the first great civilisations, like Egypt. Could it possibly be real? After exhaustive tests, the disc was declared genuine. Then a team of crack scientists pieced together what it meant. What emerged is a true marvel. This disc, it seems, is a Bronze Age Bible, combining an advanced understanding of the stars with some of the most sophisticated religious imagery of the age. In intellectual achievement and also age, it surpasses anything yet found in Egypt or Greece. It seems that civilisation had already dawned in Europe.

Air Date: 2004-01-29

5  The Dark Secret of Hendrik Schön

Imagine a world where disease could be eradicated by an injection of tiny robots the size of molecules. That is the hope offered by nanotechnology - the science of microscopically small machines. But others fear nanotechnology could lead to a non-biological cancer - where swarms of tiny nanobots come together and literally devour human flesh. Sounds like science fiction? It certainly did until a brilliant young scientist called Hendrik Schön seemed to bring it a step closer. Schön's great breakthrough was to make a computer transistor out of a single organic molecule. It was an achievement of almost incalculable brilliance. Some speculated this technology could spell the end of the entire silicon chip industry. Crucially, Schön's transistor was organic. Suddenly, this seemed to be the first step towards true nanotechnology, where minute computers could grow as living cells. Scientists speculated about how these tiny machines could be used to target diseases with astonishing precision. Others wondered - could the military use them as a new weapon? Others, including Prince Charles, were terrified. If these machines can grow by themselves, how do we stop them from growing? What happened next would destroy reputations and shatter lives - because there was more to Hendrik Schön's discovery than anyone knew.

Air Date: 2004-02-05

6  Thalidomide - A Second Chance?

Thalidomide was one of the biggest medical tragedies of modern times. The images of children born with shrunken limbs still haunt anyone who sees them. And the tragedy is not over. Those children are adults today, still coping with their disability. For many, thalidomide is a drug that should be consigned to the dustbin of history - an awful cautionary tale of the errors that science can make. But now it is making a comeback - as a radical treatment for incurable blood cancers. But can it possibly be safe to use such a dangerous drug again? In a powerful and deeply moving film, Horizon tells the tale of thalidomide and how this drug that has become so infamous may now be giving hope to people who otherwise face death. It also explores the mystery at the heart of thalidomide. It seems that the reason why it works for cancer may at least partly explain something that has long baffled scientists - why thalidomide caused such terrible damage to babies in the womb all those years ago.

Air Date: 2004-02-12

7  Diamond Labs

Top quality diamonds at knock down prices? The only catch is: these rocks don't come out of the ground, but are made in a lab. This is the promise offered by a series of recent scientific breakthroughs. For most of us, it seems we may soon be able to bejewel ourselves like movie stars. But for De Beers, the world's largest diamond trader, could this, one day, be a serious threat? Following a dodgy meeting in Moscow, retired US Army General Carter Clarke acquired some experimental diamond growing machines, originally destined for the Russian military. He created the world's first gem diamond production line, to mass produce highly prized coloured diamonds. In a secret location south of Boston, a father and son team developed a different technique. Robert Linares and son Bryant have made colourless diamonds, allegedly higher quality than those found in nature. De Beers, at vast cost, set up a new scientific division called the Gem Defensive Programme. Its goal: to find ways to tell apart their natural diamonds from these new synthetic gems. But will the new synthetics slip through De Beers detection net? And could anyone really tell the difference? Horizon tells the story of the Diamond Labs.

Air Date: 2004-03-04

8  T-Rex - Warrior or Wimp?

Tyrannosaurus rex - it's the scariest, meanest, most bewitching dinosaur of them all. Children are captivated by the sheer savagery of the teeth. Experts marvelled at the force of its bite - ten times more powerful than anything we know today. Movie makers made millions out of the terror it inspired. But could our picture of this monster be completely wrong? Was T. rex in fact a slow lumbering creature, with hideously bad breath, that couldn't get anywhere close to catching a Triceratops. Was it really a scavenger that lived off the scraps left by others? Was T. rex, in fact, a wimp? Featuring fabulous graphics and interviews with T. rex experts from around the world, Horizon looks at the new science that is challenging the legend of the dinosaur we love to hate.

Air Date: 2004-03-11

9  Project Poltergeist

This is the story of two genuine scientific heroes. For forty years, John Bahcall and Ray Davis were engaged in a single extraordinary experiment - to find out why the Sun shines. In the end they would triumph. Davis would win the Nobel Prize and, thanks to their work, a whole new theory about how the universe is put together may have to be created. At the heart of this story is a tiny, utterly mysterious thing called a neutrino. Trillions of them pass through your body every second, touching nothing, leaving no trace. Yet neutrinos are one of a handful of fundamental particles in the universe, essential to every atom in existence and clues to what makes the Sun work. But their ghost-like quality made trapping and understanding them immensely difficult. What then followed was a bizarre series of experiments. They led from a vat containing 600 tons of cleaning fluid, to a vast cavern in a Japanese mountain, to a hole in the ground in Canada two kilometres deep. What they would reveal would stun the world of science. It seems that neutrinos may be our parents. They may be the reason why everything, including us, exists.

Air Date: 2004-03-18

10  The Truth of Troy

It's one of the greatest stories ever told. The legend of Helen of Troy has enchanted audiences for the last three thousand years. In May this year a Hollywood film staring Brad Pitt and Orlando Bloom will be launched in Britain. But is there any reality to the myth? Horizon has unprecedented access to the scientist with the answers. Since 1988 Professor Manfred Korfmann has been excavating the site of Troy. He has never before spoken at this length. He has made amazing discoveries - how large the city was, how well it was defended and, crucially, that there was once a great battle there at precisely the time that experts believe the Trojan war occurred. But who had attacked the city and why? Horizon then follows a trail of clues - the ancient tablets written by a lost civilisation, the sunken ship rich in treasure, and the magnificent golden masks and bronze swords of a warrior people. The film reaches its climax in a tunnel deep beneath Troy, where Korfmann has made a discovery that may reveal, once and for all, the truth behind the myth. The story that emerges is one of great passion - but not, it seems, about love.

Air Date: 2004-03-25

11  The Truth About Vitamins

Every year we spend £300 million on vitamin supplements, but do they actually do us any good? Some believe they offer the promise of preventing or even curing some of the world's biggest killers, such as heart disease and cancer. Others claim that taking large doses of some vitamins may in certain cases be harmful. So what are the facts? Nearly 40 years ago, one of the greatest scientists of the 20th century and double Nobel Prize winner, Linus Pauling, revolutionised the way people thought about vitamins. He claimed that by taking huge doses of vitamin C you could prevent or even cure the common cold. He predicted that if everybody followed his advice, the common cold could even be eradicated. Many scientists dismissed his theory as quackery, but the public loved it and it helped launch a huge industry. But the latest evidence shows the great man was mistaken. Vitamin C can help you once have got a cold, but for most people it does nothing to prevent you from catching one in the first place. Even if large doses of vitamin C do not prevent the common cold, some claim that it can still offer a more profound benefit. It is one of a group of vitamins called anti-oxidants that some believe can prevent illnesses such as cancer, Alzheimer's and heart disease. In 2004, scientists in the United States claimed that people could be missing any of the potential benefits of taking one of the world's most popular anti-oxidant vitamin supplements, vitamin E, because their bodies might not be absorbing it. But our own investigation suggested that the American scientists' conclusion could be mistaken. While most safety experts believe that vitamins C and E can be taken safely even in quite large doses, there is worrying evidence that one form of another common vitamin, vitamin A, could be linked to osteoporosis, a debilitating bone disease. If the theory is right it means that a person's diet, or some supplements that they take every day to improve their health, could actually be slowly and silently weakening their bones.

Air Date: 2004-09-16

12  King Solomon's Tablet of Stone

2001. A clandestine meeting of leading Israeli archaeologists are shown a remarkable artefact. It's a stone tablet, apparently from 1,000BC. The writing on its face describes repairs to the temple of King Solomon. It is the first archaeological evidence ever found of this legendary building. The relic caused a sensation. But this was only just the start. For authentication, the tablet was taken to the Geological Survey of Israel. Here, after a battery of tests, including radiocarbon dating, scientists officially pronounced the stone to be genuine. The tests even revealed microscopic particles of gold in the outer layer of stone. These were apparently the result of the tablet surviving the fire which, according to the bible, destroyed the temple when the Babylonians sacked Jerusalem in 586BC. The stone tablet was offered for sale to the Israel Museum, home to many of Israel's greatest treasures. Rumours suggested the asking price was as high as $10million. But the museum needed to know where the stone had come from. Even its owner was a mystery. To make matters more complex, the stone itself had disappeared again. The Israeli Antiquities Authority wanted answers. A nine month search for the mysterious stranger who had first appeared with the stone eventually led them to a private detective who had been hired by a well known antiquities collector, Oded Golan. Golan insisted he too was just a front man for another collector. But the authorities were suspicious. He was known to be the owner of the James Ossuary, another extraordinary artefact which had appeared a couple of years earlier. This was a burial box with an inscription linking it to Jesus' brother. The authorities raided Golan's apartment and recovered both the ossuary and the elusive stone. It was time to establish once and for all if both were genuine. So they set up a committee of linguists and scientists to examine them. Looking at the stone, several linguists said 'fake'. Some of the Hebrew, they claimed, was not ancient. Other experts claimed that so little is known of ancient Hebrew that it's impossible to be sure. The committee turned to geology. Dr Yuval Goren, a geo-archaeologist and head of the Archaeological Institute at Tel-Aviv University, soon found evidence that a team of sophisticated forgers had led the earlier experts astray. - The patina on the stone had in fact been manufactured artificially - The charcoal particles which produced the convincing radiocarbon date had been added by hand - The gold fragments hinting at an ancient fire were a clever final addition The authorities presented their conclusions. They announced that the stone tablet, and the James Ossuary, were elaborate fakes. But who was producing these fakes and how? Dr Goren decided to piece together how the stone tablet had been made. He tracked the origin of the stone itself - apparently a building block taken from a Crusader castle. It was even possible to work out how the fake patina had been manufactured and the ingredients used. What was clear was the team of forgers included experts in a range of disciplines. When the police took Oded Golan into custody and searched his apartment they discovered a workshop with a range of tools, materials, and half finished 'antiquities'. This was evidence for an operation of a scale far greater than they had suspected. Investigators have established that collectors around the world have paid hundreds of thousands of dollars for artefacts that came through Oded Golan's associates. Dozens of these items have now been examined by Dr Goren, and all have been revealed to be forgeries. Police now suspect that artefacts made by the same team of forgers have found their way into leading museums around the world. Some archaeologists have now concluded that everything that came to market in the last 20 years without clear provenance should be considered a fake. Many of these objects, like the stone tablet which started the investigation, were cynically playing on the desire of many of the collectors to see the bible confirmed as history. For those in search of the temple of Solomon - their goal is as far away as ever.

Air Date: 2004-09-23

13  Derek Tastes of Earwax

Is Wednesday red? Take part in our experiment to test whether your senses overlap. Do melodies have a colour? Take part in our experiment to test whether you hear colours. Imagine if every time you saw someone called Derek you got a strong taste of earwax in your mouth. It happens to James Wannerton, who runs a pub. Derek is one of his regulars. Another regular's name gives him the taste of wet nappies. For some puzzling reason, James's sense of sound and taste are intermingled. Dorothy Latham sees words as colours. Whenever she reads a black and white text, she sees each letter tinged in the shade of her own multi-coloured alphabet - even though she knows the reality of the text is black and white. Spoken words have an even stranger effect. She sees them, spelled out letter by letter, on a colourful ticker tape in front of her head. Both James and Dorothy have a mysterious condition called synaesthesia, in which their senses have become linked. For years scientists dismissed it, putting it in the same category as séances and spoon-bending. But now, synaesthesia is sparking a revolution in our understanding of the human mind. Two synaesthetes seldom agree on the colours or tastes they experience. While Covent Garden may taste of crinkly chocolate to James, it's very unlikely to have the same taste for another synaesthete. And Dorothy's brother Peter, also a synaesthete, won't see M or Z in the same colour as she does. But despite these differences, scientists are now beginning to discover more and more overarching synaesthetic patterns. Dorothy doesn't only see letters and numbers in colour. Music produces a riot of colour, too. As Dorothy hears notes going from low to high, her colours change from black and purple to mid-browns and then yellows and whites. Overall, lower notes evoke darker colours and higher notes brighter colours - and this pattern is true for most synaesthetes. But surprisingly, when non-synaesthetes are asked to match colours and music, they show a similar pattern. Most of us seem to associate low notes with darker colours and high notes with brighter colours. The evidence of the synaesthete in all of us doesn't end here. Another clue comes from the way we manipulate numbers. More than half of all synaesthetes who see coloured numbers also experience their numbers arranged in space around them. Heather Birt is such a synaesthete, and she's followed by a stream of numbers wherever she goes. Recently, scientists started to investigate how non-synaesthetes deal with numbers. They found they're better at manipulating small numbers with their left hand, and their bigger numbers with our right hand. This suggests that we all somehow think of numbers as arranged in space, even if we're not aware of it. More evidence, it seems, that we're all synaesthetic to some degree. It's just that some people experience a more exaggerated version. A few scientists believe that synaesthesia might even explain how we evolved two of the traits that define our species and have transformed our world - creativity and language. Many famous artists have been synaesthetes - the jazz legend Miles Davis, for instance, and the painter Kandinsky. In fact, a number of studies suggest that synaesthesia may be more common among artists, poets and musicians. This has led some scientists to argue that synaesthesia and creativity may share a similar basis - that both may be down to brain processes that involve linking two seemingly unrelated areas. Some believe that our common synaesthetic abilities may also have been the springboard to language. Connections between our senses of hearing and vision, for example, could have been an important initial step towards the creation of words. Our earliest ancestors may have first started to talk by using sounds that actually evoked the object they wished to describe. According to this theory, language could have emerged from the multitude of synaesthetic connections within our brains.

Air Date: 2004-09-30

14  What Really Killed the Dinosaurs?

Until recently most scientists thought they knew what killed off the dinosaurs. A 10km-wide meteorite had smashed into the Yucatan peninsula in Mexico, causing worldwide forest fires, tsunamis several kilometres high, and an 'impact winter' - in which dust blocked out the sun for months or years. It was thought that the dinosaurs were blasted, roasted and frozen to death, in that order. But now a small but vociferous group of scientists believes there is increasing evidence that this 'impact' theory could be wrong. That suggestion has generated one of the bitterest scientific rows of recent times.

Air Date: 2004-10-07

15  Making Millions the Easy Way

In the mid-1990s, a team of American science students took on the might of the Las Vegas casinos, and came home with millions of dollars. Hard working engineering students during the week, they became high-rolling gamblers by the weekend and proved that, in one game at least, the house doesn't always win. The game was blackjack, and the students were from the world-renowned Massachusetts Institute of Technology (MIT). Their audacious winnings marked the climax of an arms race between casino and player that began 40 years earlier with maths professor Edward Thorp. He realised that the one feature of blackjack that made it different from other casino games also made it possible to beat. In most gambling games - roulette, dice, slot machines, the lottery - events in the past do not determine the future. The odds are the same on every roll of the dice or spin of the wheel. Winning streaks or losing streaks may occur, but they are only one possible result from the set of all possible outcomes. A fair coin that has shown heads ten times, still only has a 50% chance of showing heads on the next flip. Casinos and bookmakers make certain that the odds are always stacked slightly in their favour. In other words, over time, the house will always win.

Air Date: 2004-10-14

16  Saturn - Lord of the Rings

With its famous rings, Saturn is the most distant planet clearly visible to the naked eye. But how did the rings get there and when were they formed? To study the planet in detail, scientists needed to get closer. So on 15 October 1997, the Cassini-Huygens spacecraft was launched. The Cassini-Huygens is one of the most ambitious spacecraft ever launched, taking seven years to reach Saturn. The mission itself consists of two separate probes. The first is the enormous Cassini probe, designed to gather information about all aspects of the Saturnian system, from its many rings to its 33 moons. The second is the Huygens probe, a smaller wok-shaped craft, attached to the side of Cassini. Its task is to plunge through the atmosphere of Titan, Saturn's largest and most mysterious moon. The project is a joint NASA, European Space Agency (ESA) and Italian Space Agency venture. It has cost $3.27 billion and involves over 17 countries. It was inspired by another successful mission- the launch of the two Voyager Deep Space probes. These left Earth in 1977, and arrived separately at Saturn in 1980 and 1981. They sent back revolutionary data, changing what scientists thought about the Saturnian system. They revealed that Saturn's rings are far more complex and dynamic than any one had ever imagined. They also suggested that the rings had been formed after the planet itself. Why? And how old were they? But the Voyager probes had to move on, past Uranus and Neptune and beyond, leaving these fundamental questions about the rings unanswered. Voyager also raised another mystery - Titan. Titan isn't just Saturn's largest moon, it is also shrouded in a thick orange atmosphere, composed mainly of nitrogen - similar to the Earth's atmosphere. Finding a place so far away which shared features with our own world was exceptionally tantalising. The building of the Cassini-Huygens project began in 1990. The Cassini probe was named after the French-Italian astronomer Jean-Dominique Cassini (1625-1712). Its job was to fly to Saturn, and remain in orbit around the planet for four years. The Huygens probe, named after Christiaan Huygens (1629-1695) who first discovered Titan, was to detach itself from Cassini and gather crucial information about the chemical composition of the moon's atmosphere and to reveal what kind of landscape lay beneath the clouds. Not surprisingly, the probes were armed with a formidable array of instruments. Cassini is capable of measuring everything from the planet's huge magnetosphere to tiny particles of cosmic dust. At the heart of the mission are the cameras - the so-called Imaging Science Subsystem. These have both a long and short focal length, which gives both high resolution pictures and the wider context. Cassini also carries a set of spectrometers which look at the same things as the cameras, but which can see wavelengths beyond those visible to the human eye. These wavelengths allow the spectrometer to deduce the chemical composition of whatever is being looked at. The combined weight of the two probes was a massive 5,712kg and it was to travel across a billion miles of space. This created a whole new set of problems - how to get such a massive craft to its destination. The mission planners turned to a technique known as a 'gravity assist'. The probe was to be launched by the largest rocket in the world, the Titan IVB. But that was just enough to get it out into space. Cassini was then routed by other planets, 'stealing' energy from their orbital momentum. The result is a kind of gravitational slingshot. After launching in 1997, Cassini passed by Venus twice, then Earth in 1999 and finally Jupiter at the end of 2000. On 30 June 2004, the spacecraft finally arrived at Saturn, having clocked up a speed of over 80,000km/h (approximately 50,000mph). But to get into orbit around the planet, Cassini-Huygens had to pass between Saturn's F and G rings. Mission planners had plotted a course through what appeared to be a gap, but if Cassini was hit by even a tiny particle the size of a grain of rice, the probe could be destroyed. At 19:36 Pacific Daylight Time (PDT), scientists waited anxiously at the Jet Propulsion Laboratory in California, as the manoeuvre (called Saturn Orbit Insertion) began, and Cassini fired its main engine to get into orbit. All eyes followed the signal given out by Cassini's low-gain antenna. At 21:12 PDT, the signal flattened out, indicating that Cassini-Huygens had successfully got into orbit around Saturn. The mission will last for at least four years, with the possibility of going on for longer. Cassini will use its wealth of instruments to study the whole Saturnian system. It's already providing intriguing information. One of the instruments onboard Cassini, the Ultraviolet Imaging Spectrograph (UVIS), will help scientists answer the question of how old the rings are. By looking at the reflected light in ultra-violet wavelengths, this instrument can tell what parts are icy and what parts have been contaminated. By measuring this over time, UVIS will be able to use the pollution like a clock. The dirtier the rings get, the older they are. As Cassini passed over the rings during Saturn Orbit Insertion, UVIS took images of the rings which showed a significant difference in the levels of water ice and contaminants. It will take scientists time to decipher this data, but along with the information from Cassini's other instruments, such as the Visible and Infrared Mapping Spectrometer (VIMS), they will be able to build up a picture of the composition of the rings over time, and so work out how old they are. But while the Cassini mission is due to last for years, the Huygens mission is much more short-lived. It will be key to our understanding of Titan, Saturn's largest moon. Like the Earth's, Titan's atmosphere is mainly made up of nitrogen, but there are other compounds such as methane which open up exciting possibilities for science. Because Titan is so cold (as it is so far away from the sun), methane can exist in all three states - gas, liquid and solid. Indeed methane might adopt the role water has on earth in a weather cycle, so there could be clouds of methane, methane rain, and possibly even lakes, or seas. The surface itself is probably made not of rock, but hard water ice surface. Scientists expect it to be pitted with impact craters and even volcanoes, spewing liquid water, rather than lava. So in some ways, Titan's landscape might seem strangely familiar. But crucially, Titan may also offer a window on the distant past, as scientists believe that its atmosphere may resemble the early Earth's atmosphere, before life began. It's all because the methane and nitrogen in Titan's atmosphere combine together to create a compound called tholins, which form the impenetrable orange haze that blocks Titan's surface from view. Experiments on Earth have shown that tholins, when combined with liquid water, can form amino-acids, which can then form proteins - the building blocks of life itself. While Titan is too cold to have liquid water for long on its surface, if there are volcanoes these could hurl water onto the surface of Titan from the liquid mantle beneath the surface. This may stay liquid for long enough for complex organic molecules to form. The hope is that these conditions could make Titan a planet-sized laboratory in which we can study the processes by which life might have begun on our planet. But scientists can only hypothesise at this stage since so little is known about Titan. But on 14 January 2005, we will know much more. Huygens will separate from Cassini on Christmas Day 2004, and after a 22-day coast it will enter Titan's thick atmosphere. Its enormous heat shield will protect it from searing temperatures of up to 1,700ºC, and a series of parachutes will slow its descent. After the heat shield is ejected, the instruments will begin to do their work - the onboard camera will take the first ever images from beneath the haze, and the chemical analysers will sample the atmosphere, sending back precious information about this unexplored moon.

Air Date: 2004-10-21

17  The Hunt for the Supertwister

On 3 May 2003 a tornado smashed through two suburbs of Oklahoma City. It had struck at the height of the tornado season, yet residents were still shocked by the destruction it wrought. Eight thousand homes were destroyed, a billion dollars of damage was wreaked and 40 people lost their lives. What had hit Oklahoma City that day was not just any old tornado - it was a super-twister. Tornadoes are classified on the Fujita scale, or F-scale. Most tornadoes that occur around the world can be classified on the lower reaches of the scale - the F0s, F1s or F2s. These can still cause damage and have winds in excess of 160km/h. Supertwisters are an altogether different beast. Terrifying and destructive, at their most extreme they are powered by wind travelling in excess of 480km/h. This is strong enough to lift strong framed houses from their foundations and seriously damage even reinforced concrete. Every year hundreds of people around the world are killed or injured by supertwisters. Yet what makes them even more terrifying is that it is practically impossible to predict their appearance or movement. Why they form in the first place remains a mystery. Most US tornadoes occur in Tornado Alley, a flat mid-western stretch from Texas in the south to the Dakotas in the north. High season for supertwisters tends to be during spring, from March to June. Tornadoes usually appear during a thunderstorm. Supertwisters are associated with super-cells, the largest thunderclouds of all. These are enormous rotating columns of air that can be over 30km across and 18,000 metres high - twice the height of Mount Everest. All tornadoes form when warm, moist air is pushed upward by a mass of cold air. This creates an updraft within the stormcloud that can cause a large mass of circulating air. When this air comes in contact with the ground it becomes a tornado. What is not known is precisely what triggers this final stage to form a tornado... A group of scientists are trying to plug these gaps in our knowledge. These 'storm chasers' take their lives in their own hands every time they go out in the field. To get the crucial data they need to get close to the supertwisters. Their research is vital to finding a way of giving people a few extra minutes warning. The time might not be enough to save houses or possessions, but could save lives. To help them, they use the very latest technology. Many of them, like Howie Bluestein from the University of Oklahoma, track storms using a Doppler radar dish mounted on the back of a truck. Doppler radar uses sound waves to sense the movement of air and moisture in remarkable detail - it is the most accurate way of mapping the swirling wind patterns that make up a tornado. Many storm chasing teams use at least two of these trucks so they can record information on the storm from different angles. But even with all the latest equipment, storm chasers consider themselves lucky if they intercept one or two tornadoes each year. Gathering the data is one thing, working out what to do with it is another problem altogether. Much of the work uses specially designed computer models. Lou Wicker and his colleagues from the University of Illinois have spent the past decade developing state-of-the-art software that will help to explain precisely how a tornado forms. Some of his latest work involves working out how to visualise a storm using real tornado data, picked up from the storm chaser's Doppler radar. He added the real wind speeds, atmospheric pressure and humidity present before a storm into his model. Could this model use the data to make an artificial tornado within his computer? If possible, he should be able to observe the inner workings of the twister and therefore see what had triggered the final touch down. Wicker and his colleagues soon noticed something crucial - the simulation showed a clear hook of wind and a strong downdraft. His model also showed that just as the storm was intensifying a series of whirlwinds were forming at ground level. These tiny corkscrews of wind merged together into a much larger current and seemed to form the tornado itself. The whirlwinds which showed up in the computer were so subtle that in reality they would be invisible to the naked eye. What seemed to make Wicker's work so exciting was that these mini-whirlwinds had shown up on real tornadoes picked up by both Bluestein's and fellow supertwister expert Dr Josh Wurman's radar. Could identifying these tiny whirlwinds in advance be the key to finding the extra time in tornado prediction?

Air Date: 2004-10-28

18  Dr Money and the Boy with No Penis

On 22 August 1965 Janet Reimer was granted her dearest wish: she gave birth to twins. The two boys, Brian and Bruce, were healthy babies, but they would lead tragic lives, blighted by one scientist's radical theory. When they were seven months old, the boys, who lived in Winnipeg, Canada, were sent to the local hospital for a routine circumcision. Unfortunately the doctor in charge of the procedure was using electrical equipment, which malfunctioned several times. On the last trial, Bruce's entire penis was burnt off. Brian was not operated on. The family were distraught. In the Sixties plastic surgery was not an option: even today it is not recommended that new-borns undergo penis reconstruction operations. It wasn't until several months later that Janet and her husband, Ron, saw a television programme that gave them some hope. Dr John Money, a highly renowned sexologist, featured in a debate about sex change operations on transsexuals. He had brought a transsexual with him who was convincingly feminine looking. Perhaps, thought Janet Reimer, this was the solution - they could turn their baby son into a daughter. She wrote to Dr Money immediately. He responded swiftly and invited them to come and visit him in Baltimore, Maryland. Dr Money is a highly intelligent, well respected, charismatic individual. He suggested to the Reimers that they bring their son up as a girl. Thus, when Bruce was 18 months old, he was castrated and a rudimentary vulva was created for him. The family now called him Brenda and tried to treat him like a little girl. Dr Money was the answer to the Reimers' prayers, but they were the answer to his too. He had studied people known then as hermaphrodites, now referred to as intersex, who are physically both male and female. As it was surgically easier to turn these people into females, this was standard practice. Dr Money had used case studies of hermaphrodites to show that there was a window of opportunity for surgery - a 'gender gate' - which lasted up to the age of two. During that period, he argued, if the parents chose the sex of the child, the way they brought it up would determine the child's gender, not its physical characteristics. But until this point, Dr Money had never put his controversial theory into practice with a non-intersex child. Now he had the perfect and unplanned opportunity to do so: a set of identical twins, two biological boys, one of whom could be raised a girl. Janet Reimer wrote to Dr Money of Brenda's progress and once a year the whole family visited him in Baltimore. When Brenda was five Dr Money started to publish her case - disguising her by referring to her as Joan/John - in his books. The case became a sensation. It was the proof that feminists in particular were looking for. It was proof, they argued, that there was no biological reason that boys are better at maths and that men should earn more than women. Nurture not nature determines whether we feel feminine or masculine. Widely cited in many text books, the case was a landmark study - hailed as proof of the overwhelming force of nurture - in spite of increasing evidence that hormones both in the womb and throughout a child's life, play a huge part in an individual's perception of themselves as masculine or feminine. Meanwhile, back in Canada, things were not so good for the Reimer family. Brenda behaved in a distinctly masculine fashion. She liked running and fighting and climbing and loathed playing with dolls. She had no friends and was increasingly lonely as her twin Brian was embarrassed to play with her in front of his other friends. She hated going to visit Dr Money. He insisted that to fully understand that she was a girl, she needed to grasp the difference between men and women, and frequently spoke to her about her genitalia. He took photographs of her and her brother naked. He tried to persuade her to have a vagina constructed, which, at the time, would have been made out of section of her bowel or else from the skin of her thigh, which would then be inserted into the pelvic region. He showed her graphic photographs of a woman giving birth when she was seven years old in an attempt to get her to agree to having a 'baby-hole' made. He also suggested strongly that she take hormone tablets in order to make her grow breasts when she was 12. Other scientists, including Dr Money's ex-students, argue that he did these things in the best possible interests for his patient - to make her believe that she was indeed a girl. Brenda however felt traumatised and became suicidal. Finally when she was 13, the family told her and Brian the truth. Brenda was intensely relieved as she had felt she was going insane. Almost immediately she turned herself back into a boy and called herself David. David received compensation money for the circumcision and used this to pay for surgery to have a new penis constructed. In his early twenties he met Jane Fontane, who had three children of her own, and they married. Unfortunately, his relationship with his brother worsened. Brian had felt that David, as Brenda, had received all the attention when they were growing up; once he discovered that he was no longer the only boy in the family, he became extremely angry. It was the start of mental disturbance that would develop into schizophrenia. After two failed marriages, he died, possibly of a drug overdose, which may have been a suicide attempt. David had never managed to complete his education and had to take semi-skilled work. He was made redundant and was unemployed for a year. He sold the movie rights to his story, but lost the money when a business man absconded with his investment. Stricken with grief for his brother, his marriage started to fail. Jane asked him for a short separation period, but David took this very badly. He returned to his parents' house for a few days, before driving to a supermarket car park on 4 May 2004 and shooting himself in the head. He was 38 years old. Dr Money argues that he cannot be held to blame because David did not accept a female gender identity. He says that the family delayed making a decision until their son was almost two, just before the gender gate was about to shut. Others, however, argue that he could have admitted he made a mistake when the case clearly was not working, for he continued to let people believe that it had been successful long after he had stopped seeing Brenda and she had become David. It is, perhaps above all, a cautionary tale of what may happen when a scientist falls in love with a beautiful theory and ignores the ugly facts.

Air Date: 2004-11-04