Outer space is starting to get crowded. Private companies like Elon Musk’s SpaceX and Jeff Bezos’ Blue Origin are launching rockets regularly, thousands of satellites now orbit Earth, and celebrities like Katy Perry are signing up for space tourism.

There’s talk of more missions to the Moon, and Elon Musk is even hoping for human landings on Mars, within the next decade. But while space tech is racing ahead, the laws that govern it are lagging behind. In fact, there’s only one major international law, the Outer Space Treaty - but that was made ages ago in 1967.

In this episode we hear from three people studying space law; Andre Kwok, a recent graduate at the Australian National University, and Judith Jahnke from Sweden and Martina Elia Vitoloni from Argentina, both at McGill University in Canada. And BBC journalist Freya Scott-Turner explains what laws we already have and why it’s been difficult to agree on more.

Archive material provided by British Pathé.

Instagram: @bbcwhatintheworld Email: whatintheworld@bbc.co.uk WhatsApp: +44 330 12 33 22 6 Presenter: Hannah Gelbart Producers: Freya Scott-Turner and Julia Ross-Roy Editor: Verity Wilde

What if countries could sue each other for wrecking the climate? Well, that’s now a real possibility after a decision by the UN’s top court, the International Court of Justice (the ICJ). The court made the decision after a group of young law students from low-lying Pacific islands on the frontlines of climate change started a campaign in 2019. But critics say it will be hard to untangle who caused what when it comes to climate change — and that they’re already making good progress when it comes to reducing harm to the environment.

BBC Climate and Science Correspondent Georgina Rannard talks us through what this decision means and how it could impact future climate cases. And we hear from two of the young campaigners who helped bring this case to the ICJ, who tell us what this decision means to them and their communities.

Instagram: @bbcwhatintheworld Email: whatintheworld@bbc.co.uk WhatsApp: +44 330 12 33 22 6 Presenter: Hannah Gelbart Producers: Emily Horler and Chelsea Coates Editor: Verity Wilde

Period tracking apps help you track your menstrual cycle, so you know when to expect your period. They’re growing in popularity worldwide, with the three most popular ones racking up over 250 million downloads between them. But studies show that some women might also be using them to avoid getting pregnant.

One of the apps, Natural Cycles, has been approved in the US to be used as a contraceptive. The company claims it is 93% effective at preventing pregnancies, when used perfectly. So why are more people turning to these apps? Are they safe to use as a contraceptive and what are the risks?

Sexologist Rayka Kumru from Turkey explains why these period tracking apps are becoming so popular and the privacy concerns around using them. Dr Francesco Rampazzo, a lecturer in Demography at the University of Oxford, tells us more about where period tracking apps are getting the most downloads.

Instagram: @bbcwhatintheworld Email: whatintheworld@bbc.co.uk WhatsApp: +44 330 12 33 22 6 Presenter: Hannah Gelbart Producers: Chelsea Coates, Benita Barden and Emilia Jansson Video Journalist: Baldeep Chahal Editor: Harriet Oliver