Switzerland has submitted a proposal to create a United Nations expert group on solar geoengineering to inform governments and stakeholders. The idea was discussed at the UN Environment Assembly in Nairobi, Kenya, this week. Professor Aarti Gupta shares how, after tense negotiations, the different member states could not agree, and the proposal was withdrawn. Why is solar geoengineering a controversial issue? How would dimming the sun even work? And should we consider it a genuine option in our fight against climate change? Dr Pete Irvine and Professor Joanna Haigh join presenter Marnie Chesterton in the studio to discuss.

Animal welfare charities have been celebrating a ban on donkey skin trade, agreed to this month by 55 African countries. This will make it illegal to slaughter donkeys for their skin across the continent, where around two thirds of the world’s 53 million donkeys live. Victoria Gill tells Marnie that the demand for the animals' skins is fuelled by the popularity of an ancient Chinese medicine called Ejiao, believed to have health-enhancing and youth-preserving properties and traditionally made from donkey hides.

Lastly, Dr Jess Wade, physicist and science communicator at Imperial College London, discusses Breaking Through: My Life in Science. It’s the memoir of Nobel Prize-winning biochemist Dr Katalin Karikó, whose passion and dedication to mRNA research led to the development of the life-changing COVID mRNA vaccines.

Presenter: Marnie Chesterton Producers: Florian Bohr, Louise Orchard Assistant Producer: Imaan Moin Editor: Martin Smith Production Co-ordinator: Jana Bennett-Holesworth

BBC Inside Science is produced in collaboration with the Open University.