On the 15th December, Tim Peake will launch into space to be Britain's first astronaut on board the International Space Station.
For the past two years, Tim has been filming a video diary for Horizon showing the risks, pressures and rigorous training required to launch into space. Horizon also talks exclusively to his wife and two children as they prepare to wave him goodbye on his voyage to space
From training in the Soyuz capsule, centrifuges, space station mockups, virtual reality and a huge pool to replicate spacewalks, to dealing with the physical dangers of weightlessness, witnessing his first launch and spending time away from his wife Rebecca and his two sons, this is an intimate portrait and remarkable insight into the world of an astronaut.

There are about 600 murders each year in the UK. So, what drives people to kill? Are some people born to kill or are they driven to it by circumstances? Michael Mosley delves into the BBC archives to chart scientists' progress as they probed the mind of the murderer to try to understand why people kill, and to find out whether by understanding murder we can prevent it.

Today, the topic of climate change is a major part of daily life, yet 40 years ago it was virtually unheard of. Since then, Horizon and the BBC have followed scientists as they have tried to unpick how the climate works and whether it is changing. Dr Helen Czerski delves into this unique archive to chart the transformation of a little-known theory into one of the greatest scientific undertakings in history.

So far, the volunteers have successfully been losing weight, but now the honeymoon period is over. It is the final two months of the diet, and their minds and bodies are fighting back. Dr Chris van Tulleken and Professor Tanya Byron find out if the new personalised diets will help them stay on course, and the experts reveal the scientific secrets to permanent dieting success.

It is time to see if personalised dieting will work in normal life. The volunteers have been given one of three diets to follow - based on their genes, their hormones and their psychology. But now they are back at home, trying to stick to their personalised diets with all the stresses and temptations of real life.

Instead of reaching for the latest fad diet, the best way to lose weight successfully is a personalised approach - diets tailored to your individual biology and psychology. In a groundbreaking national experiment, Dr Chris van Tulleken and Professor Tanya Byron join a team of leading experts to put 75 overweight volunteers on diets designed to tackle the specific reasons why they eat too much.