Discovery

Fixing the nitrogen fix. Roland Pease asks whether after a hundred years of the old industrial process, there’s a better way of making nitrogen fertilisers. Nitrogen is one of the most important elements for life, and we’re virtually swimming in it – the atmosphere is four fifths nitrogen gas. And yet nitrogen is one of the hardest elements for life to capture – it’s a molecule that’s almost completely inert. But can chemists copy nature’s tricks to ensnare this elusive molecule, using gentle reactions and without harming the environment in the process.

Roland Pease looks into the new discipline of Green Chemistry, which seeks to improve our world, without doing harm at the same time. Since before the industrial revolution, chemistry has been transforming our lives, and the world around us, giving us medicines, materials, the fuels to make things happen, and the fertilisers and pesticides to boost our crops. But for many that progress has also brought damage in the form of pollution and contamination of the planet. Green chemistry could change all that.

Veteran astronaut Jeff Hoffman looks back on 30 years of the Space Shuttle and asks how US astronauts will get into space after it is gone

Adam Hart explores the science and history behind honey and the bees that make it. Honey is amazing stuff. Made by an insect, the honeybee, it is a long-term storage product that keeps them alive throughout the winter, but its physical, biological and chemical properties make it very useful for us too. A sweet treat, a part of our culture, a feature of our holy books and a component of our medicine cabinets, honey has been an important part of our history, but will it have a role in our future?

Gabrielle Walker investigates how the thin veil of our atmosphere protects life on Earth from the hazards of deep space

Earth's atmosphere is both sustainer and destroyer of life. Gabrielle Walker discovers surprises in how it does so

We not only live in the air, we live because of it. And air is about much more than just breathing. It is a transformer and a protector, though ultimately also a poison. Gabrielle Walker experiences air – floats in it, flies in it, weighs it and discovers that 'Thin Air' packs one of the most powerful forces on the planet.

Trevor Cox explores how percussion and string instruments make their own particular sounds

Trevor Cox examines the science of wind instruments.

Trevor Cox examines how the human voice makes sound.

In the second of two programmes about nanotechnology, Richard Hollingham concentrates on the environmental uses for nanotechnology, especially water and energy generation. Professor Eugene Cloete from Stellenbosch University has developed a water filter that looks like a teabag and which uses nanofibres to filter out contaminants. Researchers at the University of Brighton are developing ways of purifying large amounts of water at source. Scientists at the University of Cambridge are developing thin films of nanocrystals that capture sunlight and turn it into electrical energy. As nanoparticles become more widely used, there’s growing concern about their safety. Richard talks to Professor Ian Colbeck from Essex University and Richard Denison from the Environmental Defence Fund about the potential risks posed by nanoparticles if they escape into the environment.

In the first of two programmes about nanotechnology, Richard Hollingham investigates how a better understanding of the properties of nanoparticles is helping researchers develop novel medical treatments. He talks to Dr Simon Holland and Wendy Knight at GlaxoSmithKline about research into using nanoparticles to deliver therapeutic agents to precise locations in the body. Richard also visits MagForce, a German research company, that's developing a novel therapy using heated nanoparticles of iron oxide to destroy brain cancers.

The blogger and the author of Bad Science, Dr Ben Goldacre, himself a defendant in a lengthy and costly legal case, explores the battle to keep libel out of science and what it might mean for us and the future of medical research if that battle is lost.

As world leaders gather in Cancun for the latest UN climate negotiations, the Climate Connection series asks a key question in the story of action on climate change: what's stopping us? In part three Jon Stewart considers if the lack of action is down to a failure of communication

What is the secret of pleasure? And why do some people seem to experience more of it than others? A.C.Grayling talks to Morten Kringelbach, a neuroscientist who is exploring how the brain processes pleasure and how that relates to happiness.