In the news pod, 4 years on from the outset of the COVID pandemic, what questions still need answering in the bid to avoid a similar emergency? Plus, why we need to start taking space security more seriously, how car brakes could be more polluting than exhaust fumes, and Paul Alexander - who lived inside an iron lung for 70 years - dies at the age of 78. Like this podcast? Please help us by supporting the Naked Scientists