Horizon Season 52 Episodes

Episode 1

What's the Right Diet for You? - Pt I

Dr Chris van Tulleken and Professor Tanya Byron join a team of experts to put 75 overweight volunteers on diets designed to tackle the specific reasons why they eat too much.

Episode 2

What's the Right Diet for You? - Pt II

Experts put overweight volunteers on diets designed to tackle the specific reasons why they eat too much. It is time to see if personalised dieting will work in everyday life.

Episode 3

What's the Right Diet for You? - Pt III

Experts put overweight volunteers on diets tackling the specific reasons why they eat too much. In the final two months of the diet, the volunteers' bodies are fighting back.

Episode 4

Secrets of the Solar System

59 mins

New planets are now being discovered outside our solar system on a regular basis, and these strange new worlds are forcing scientists to rewrite the history of our own solar system. Far from a simple story of stable orbits, the creation of our solar system is a tale of hellfire, chaos and planetary pinball. It's a miracle our Earth is here at all.

Episode 5

Climate Change: A Horizon Guide

Dr Helen Czerski delves into the Horizon archive to chart the transformation of a little-known theory into one of the greatest scientific undertakings in history.

Episode 6

The Mystery of Murder: A Horizon Guide

Michael Mosley uses the BBC archives to chart scientists' progress as they probed the mind of the murderer to try to understand why people kill, and whether it can help prevent it.

Episode 7

Aftershock: The Hunt for Gravitational Waves

60 mins

In March 2014, a team of astronomers stunned the scientific world when they announced that their BICEP2 telescope at the South Pole had possibly detected a signal of "gravitational waves" from the early universe. This is the inside story of the hunt for gravitational waves from the beginning of time. How the BICEP2 team came close to making one of the greatest discoveries of the century - and what happened when it all began to unravel.

Episode 8

Dancing in the Dark - The End of Physics

Scientists genuinely don't know what most of our universe is made of. The atoms we're made from only make up four per cent. The rest is dark matter and dark energy (for 'dark', read 'don't know'). The Large Hadron Collider at CERN has been upgraded. When it's switched on in March 2015, its collisions will have twice the energy they did before. The hope is that scientists will discover the identity of dark matter in the debris. The stakes are high - because if dark matter fails to show itself, it might mean that physics itself needs a rethink.

Episode 9

70 Million Animal Mummies: Egypt's Dark Secret

59 mins

The team investigate the use of modern medical technology to scan Egyptian animal mummies from museums across the world. By creating 3-D images of their content, experts are discovering the truth about the strange role animals played in ancient Egyptian belief. Horizon meets the scientists working in Egypt who are exploring the ancient underground catacombs where mummies were originally buried to reveal why the ancient Egyptians mummified millions and millions of animals.

Episode 10

Is Binge Drinking Really That Bad?

59 mins

How bad can our drinking pattern be for our health? Doctors and genetically identical twins Chris and Xand van Tulleken want to find out. With the current drinking guidelines under review, the twins embark on self-experimentation to see the effects of different drinking patterns on their health. With Chris drinking 21 units spread evenly across the week and Xand having his 21 in single weekly binges, how will their bodies differ after a month? Catching up with the latest research into alcohol drinking patterns, we ask if moderate drinking is genuinely good for us - and whether binge drinking is really that bad.

Episode 11

The Trouble with Space Junk

52 mins

In 2014, the International Space Station had to move three times to avoid lethal chunks of space debris and there is an increasing problem of satellites mysteriously breaking down. With first-hand accounts from astronauts and experts, Horizon reveals the scale of the problem of space junk. Our planet is surrounded by hundreds of millions of pieces of junk moving at 17,000 miles per hour. Now the US government is investing a billion dollars to track them, and companies around the world are developing ways to clear up their mess - from robot arms to nets and harpoons. Horizon investigates the science behind the hit film Gravity and discovers the reality is far more worrying than the Hollywood fiction.

Episode 12

Are Health Tests Really a Good Idea?

Michael Mosley puts himself through a battery of health tests available to people who feel perfectly well. From an expensive heart scan to a new national screening procedure to detect the earliest signs of bowel cancer, Mosley sets out to discover which if any of the tests are worth doing.

Episode 13

First Britons

Horizon reveals how new archaeological discoveries are painting a different picture of the very first native Britons. For centuries it's been thought that these hunter-gatherers lived a brutal, hand-to-mouth existence. But extraordinary new evidence has forced scientists to rethink who these people were, where they came from and what impact they had on our early history. Now, our impression is of a hardy, sophisticated people who withstood centuries of extreme climate change and a devastating tsunami that was to give birth to the island nation of Britain. Their way of life may even have survived beyond its greatest ever threat - the farming revolution.

Episode 14

OCD: A Monster in My Mind

Most of us think that Obsessive Compulsive Disorder (OCD) is just over fussy tidying. But it's actually much more serious. Sophie has to check that she hasn't killed people, looking for dead bodies wherever she goes, Richard is terrified of touching the bin, and Nanda is about to have pioneering brain surgery to stop her worrying about components on her body - that her eyebrow might not be aligned or that she has bad breath. Professor Uta Frith meets the people living with OCD, looks at the therapy available and asks what neuroscience can offer by way of a cure.

Episode 15

Which Universe Are We In?

44 mins

Imagine a world where dinosaurs still walk the earth. A world where the Germans won World War II and you are president of the United States. Imagine a world where the laws of physics no longer apply and where infinite copies of you are playing out every story line of your life. It sounds like a plot stolen straight from Hollywood, but far from it. This is the multiverse. Until very recently the whole idea of the multiverse was dismissed as a fantasy, but now this strangest of ideas is at the cutting edge of science. And for a growing number of scientists, the multiverse is the only way we will ever truly make sense of the world we are in. Horizon asks the question: Do multiple universes exist? And if so, which one are we actually in?

Episode 16

Cosmic Dawn: The Real Moment of Creation

Wed, Sep 9, 201552 mins

Forget the big bang. The real moment of creation was the Cosmic Dawn - the moment of first light. This is the scientific version of the story of Genesis. The big bang gets all the credit for creating our universe. But in fact, the universe it gave was dark and boring. There were no stars, no galaxies, just a vast, black fog of gas - the cosmic dark ages. But, after a hundred million years of nothing, came a dramatic moment of transformation - the Cosmic Dawn. It's the moment the first stars were born, the moment that lit up the Universe, and made the first structure and the first ingredients of life. This was the real moment of creation. Astronomers are now trying to witness the cosmic dawn. For the first time they have the tools to explore the very first stars of the universe and to tell the scientific story of our creation.

Episode 17

Are Video Games Really That Bad?

Horizon explores the differing opinions on video games. They frequently stand accused of causing violence and addiction in young people - but is there truth in the claim?

Episode 18

Tim Peake Special: How to Be an Astronaut

10 mins

Astronaut Tim Peake's video diary of the two years leading up to his arrival at the International Space Station in December 2015.