Two black holes have collided and combined in the largest merger yet observed. Mark Hannam of Cardiff University and member of the study explains how the Interferometer Gravitational Wave Observatories (LIGO) detected this ‘violent’ event through spacetime. The lifestyle of ancient humans had an impact on their risk for infectious diseases. Astrid Iversen of the University of Oxford explains how the shift away from being hunter-gatherers played a role in the origins of human pathogens.

Nitrogen fixation, or the process of organic compounds accessing nitrogen from the atmosphere via microorganisms, plays a key role in climate modelling. But prior estimations have long been missing key data to make accurate analysis. Carla Reis Ely of Oak Ridge Institute for Science and Education shares the updated facts and figures on global nitrogen fixation.

How intelligent is artificial intelligence? Can AI start discovering new scientific laws in the year? Keyon Vafa of Harvard University put several AI models to the test to see if they could discover Newton’s law of gravity and understand the world around us. Presenter: Roland Pease Producer: Imaan Moin Production Coordinator: Jana Bennet-Holesworth

(Image: Black Hole, digital illustration. Credit: Aaron Horowitz via Getty Images)