Are we alone in the universe – and if not, how many other civilisations might there be? Remarkable images and data sent back to Earth by the James Webb telescope have given a new impetus to a well-worn debate. We ask how far mathematics – and in particular a famous equation called the Drake Equation – can be used to answer one of the most fundamental questions we face. Paul Connolly investigates with the help of Catherine Heymans, Astronomer Royal for Scotland and Professor at the University of Edinburgh and Bill Diamond, President and CEO of the SETI Institute in California. Presenter: Paul Connolly Producers: Paul Connolly and Jon Bithrey Editor: Richard Vadon Production Co-ordinator: Katie Morrison Sound Engineer: David Crackles (Image: : A cluster of young stars, surrounded by clouds of interstellar gas and dust, in a nebula, located in the constellation Carina. Credit: Reuters)