Discovery

We go behind the scenes of a new exhibition on India at London’s Science Museum. What can historical objects tell us about India’s rich, and often hidden scientific past? We look at the influential mathematics, metallurgy and civil engineering of ancient India.The exhibition also contain artefacts from India’s time under the British Empire. We ask how the many years of colonial rule shaped the more recent scientific development of India. Science journalist Angela Saini presents.Image: Bakhshali manuscript, Credit: Bodleian Library

Can Africa’s Great Green Wall beat back the Sahara desert and reverse the degrading landscape? The ambitious 9 miles wide and 5000 miles long line of vegetation will stretch all the way from Dakar in the west to Djibouti in the east. Thomas Fessy is in Senegal where the wall has already begun to evolve into a series of forests and garden communities. He meets the planners, planters, ecologists and local villagers to hear how its early progress is reversing years of poor land use, turning nomads back to farmers, empowering women and creating healthy ecosystems for rain fed agriculture. But can it meet its ambition to stabilize an unstable region, reverse the growing trend of migration, fight the effects of climate change and ensure this big African dream doesn’t die in the sand?Picture: The Great Green Wall, credit: BBC Producer Adrian Washbourne

Can we Control the Dark Side of the Internet?The Internet is the world's most widely used communications tool. It’s a fast and efficient way of delivering information. However it is also quite dumb, neutral, treating equally all the data it passes around the world. From data that forms scientific research papers, the wealth of social media to keep us all connected with friends and relatives, entertainment or material we would rather not see- from political propaganda to horrific violence, the Internet makes no distinction. Is it time to change that? And can we? In this programme Aleks Krotoski looks at whether it’s possible to use technological fixes to regulate the internet or whether a more political approach is needed to governance of this vital but flawed communications medium.Picture: Human Hand Using Application on Mobile Phone, Credit: Onfokus

With the coming of the World Wide Web in the 1990s internet access opened up to everybody, it was no longer the preserve of academics and computer hobbyists. Already prior to the Web, the burgeoning internet user groups and chat rooms had tested what was acceptable behaviour online, but access was still limited. Aleks Krotoski asks whether the Web through enabling much wider use of the internet is the villain of the piece in facilitating not just entertainment and commerce, but all aspects of the darker side, from malicious computer hacking attacks, worms and viruses, to new channels for criminality, online extortion and identity theft.(Photo: Internet sign. Credit: code6d)

Just how did the Internet become the most powerful communications medium on the planet, and why does it seem to be an uncontrollable medium for good and bad? With no cross border regulation the internet can act as an incredible force for connecting people and supporting human rights and yet at the same time convey the most offensive material imaginable. It has become the most useful research tool on earth but also the most effective way of delivering threats to the security of governments, the health service and on a personal level our own identities.In this series Aleks Krotoski unravels the complexity of the internet, meeting the people who really invented it, looking behind the myths and cultural constructs to explain what it actually is and how it came to exist outside of conventional regulation. We’ll ask whether the nature of the net itself really is cause for concern - and if so what can be done to reign in the negatives of the internet without restricting the positives? In this first episode we go back to the days before the internet to look at the cultural and technological landscape from which it grew, and unravel some of the key moments - now lost in time and obscured by technology folklore, which mark when the internet lost its innocence.Picture: Mechanical computer keyboard blurred, credit: OSchaumann/Getty

Silicon is literally everywhere in both the natural and built environment, from the dominance of silicate rocks in the earth crust, to ubiquitous sand in building materials and as the basis for glass. We've also harnessed silicon's properties as a semiconductor to build the modern electronics industry - without silicon personal computers and smartphones would simply not exist.Silicon is also found widely across the universe. It is formed in stars, particularly when they explode. And the similarities between how silicon and carbon form chemical bonds has led many to wonder whether there could be silicon based life elsewhere - perhaps in some far flung part of the galaxy where carbon is not as abundant as here on earth. As well as discussing the potential for silicon based life on other planets, Birkbeck University astrobiologist Dr Louisa Preston considers the varied uses of silicon here on earth, from its dominance in our built environment to its driving role in artificial intelligence and its ability to harness the sun's energy.Image: Lump of silicon on solar panels Credit: wloven/Getty Images

For the first time in almost 100 years the USA is experiencing a full solar eclipse from coast to coast on August 21st 2017.Main image: Totality during the solar eclipse at Palm Cove on November 14, 2012 in Palm Cove, Australia. Credit: Ian Hitchcock / Getty Images

Carbon is widely considered to be the key element in forming life. It's at the centre of DNA, and the molecules upon which all living things rely.Monica Grady, Professor of Planetary Science at the Open University, explores the nature of carbon, from its formation in distant stars to its uses and abuses here on earth. She looks at why it forms the scaffold upon which living organisms are built, and how the mechanisms involved have helped inform the development of new carbon based technology, and products - from telephones to tennis rackets.One form of carbon is graphene which offers great promise in improving solar cells and batteries, and introducing a whole new range of cheaper more flexible electronics.Carbon is also the key component of greenhouse gases, carbon dioxide and methane. To counter some of the effects of man-made climate change, Scientists are now developing novel ways to speed up this mechanism - using waste materials created from mining and industry.Monica Grady also looks to space, and the significance of carbon in the far reaches of the universe. There is lots of carbon in space, some in forms we might recognise as the precursors to molecules. As elemental carbon seems to be everywhere what are the chances of carbon based life elsewhere?Image: Steam and exhaust rise from the chemical company Oxea (front) and the coking plant January 6, 2017 in Oberhausen, Germany. Photo by Lukas Schulze Getty Images

From the origins of the universe, though batteries, glass and grease to influencing the working of our brains, neuroscientist Sophie Scott tracks the incredible power of lithium.It's 200 years ago this year that lithium was first isolated and named, but this, the lightest of all metals, had been used as a drug for centuries before. From the industrial revolution it proves its worth as a key ingredient in glass and grease, and as the major component in lithium ion batteries it powers every smartphone on the planet. In mental health lithium has proved one of the most effective treatments. And its use to treat physical ailments is now making a comeback.We explore how the chemistry of lithium links all these apparently unrelated uses together.Main Image: Lights from mobile phones in Bucharest on February, 2017. Credit: ANDREI PUNGOVSCHI / AFP / Getty Images )

Oxygen appeared on Earth over two billion years ago and life took off. Now it makes up just over a fifth of the air. Trevor Cox, professor of acoustic engineering at the University of Salford, England, tells the story of oxygen on Earth and in space. Without oxygen, there would be no life on Earth, yet it was not discovered until late in the 18th Century. During the Great Oxidation Event, three billion years ago, cyanobacteria, thought to be the earliest forms of life on our planet, started to photosynthesise and these tiny creatures were responsible for putting the oxygen into our atmosphere, so we can breathe today. But it is not just for breathing. Ozone is three atoms of oxygen, and when it is in the stratosphere it stops harmful UVB rays from the sun reaching us. And if we are ever to leave our home planet, we will need to find a way to generate enough oxygen to keep us alive. Trevor visits the Science Museum in London, to discover how astronauts on the space station get their oxygen. Trevor Cox is not only an acoustic engineer, he also plays the saxophone. When he finds out the role that oxygen, in the air, has on the sound of his playing he gets a surprise.(Photo: Hovering clouds near Nagqu, approx 4,500 meters above sea level, north of Lhasa on the Tibetan plateau. Credit: Frederic J Brown/ AFP/Getty Images)