Having a fast and easy way to cut out and replace genes could revolutionise areas of biology as diverse as medicine and agriculture. And the discovery of the gene editing tool using CRISPR-cas9 makes that revolution a present reality. But the teams that revealed this gene editing tool piece by piece were not looking for anything to do with genetic engineering: instead they were curious to know more about how bacterial immunity works.

Presenter Adam Hart speaks with Professor Jennifer Doudna of the University of California, Berkeley, and Dr Rodolphe Barrangou of North Carolina State University to reveal the story of how scientific curiosity can accidentally change the world.

Produced by Rory Galloway. First broadcast on Friday 27 July 2018.

Before the eruption of Krakatoa in 1883, nobody knew about the invisible streams of air in the middle atmosphere that are important for air travel and meteorology.

Adam Hart explores the archives of the Royal Society in London to reveal a story of how global observations of the atmospheric effects caused by the ejected smoke from Krakatoa unexpectedly revealed the presence of the jet streams.

Produced by Rory Galloway. First broadcast on Thursday 26 July 2018.

The coelacanth is a fish that, until 1938, was only known from the fossil record until a young South African curator named Marjorie Courtenay-Latimer found one - only just deceased - on the deck of a fishing boat.

Presenter Adam Hart speaks with ichthyologists and curators who knew Marjorie, putting together the story of how a curious mind, determination and a bit of luck saved this 'living fossil' for science.

Produced by Rory Galloway. First broadcast on Wednesday 25 July 2018.

Evidence for the Big Bang at the start of the universe was discovered by accident, using technology developed to record radio waves from space, that were themselves found by accident.

Adam Hart explores serendipity in radio astronomy with Professor Nial Tanvir of Leicester University, and Professor Sarah Bridle of Manchester University, in a story involving not a small amount of pigeon poo, and a persistent odd noise detected from space.

Produced by Rory Galloway. First broadcast on Tuesday 24 July 2018.

Viagra was supposed to be a treatment for the heart condition angina, but during clinical trials an unexpected side effect was noticed by the young male participants.

Telling the story of this unexpected discovery, presenter Adam Hart speaks with the Pfizer scientists Sir Simon Campbell and Dr Peter Ellis who were part of the team that noticed the unusual side effects, and brought Viagra forward as a treatment for erectile dysfunction.

Sex journalist Alix Fox discusses the importance of this little blue pill to patients. This is the story of the accident that changed sex.

Produced by Rory Galloway. First broadcast on Monday 23 July 2018.

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.

Produced by Julian Siddle. First broadcast on Wednesday 30 August 2017.

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 chatrooms 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.

Produced by Julian Siddle. First broadcast on Wednesday 23 August 2017.

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.

Produced by Julian Siddle. First broadcast on Wednesday 16 August 2017.

Richard Dawson, Professor of Earth System Engineering at Newcastle University, was the lead author of the Infrastructure section of the UK Climate Change Risk Assessment 2017. He reflects on how he and his fellow civil engineers now view flooding from a variety of sources the main threat to our infrastructure.

Produced by Anna Buckley for the BBC Radio Science Unit. First broadcast on Friday 25 May, 2018.

Five scientists, working in different parts of the world, bear witness to some of the dramatic changes to our planet that have occurred in their lifetimes, as the global climate warms.

4. In May 2004, Professor Jennifer Leaning of Harvard University's FXB Center for Health and Human Rights, led a two-person human rights investigation into the reported widespread attacks and killings against agrarian villagers in Darfur, in Western Sudan. The villagers became refugees in neighbouring Chad. Jennifer Leaning explains how this trip lead her to realise that climate change has a crucial part to play in human migration.

Produced by Geraldine Fitzgerald for the BBC Radio Science Unit. First broadcast on Thursday 24 May, 2018.