Cardinals gathered at the Sistine Chapel yesterday, where they’ll eventually select the next pope. The decision is famously communicated through the emission of white smoke from a chimney perched on the roof of the chapel. If they haven’t reached a verdict, the smoke is black.

Interestingly, the smoke wasn’t always intended as a public signal, but became so in the late 18th century after people started scrutinising it to guess the outcome of voting. Since then, the Vatican has used several different techniques of creating smoke to give updates on the process. Mark Lorch talks us through the history and chemistry of the smoke signal.

As much of Europe celebrates VE day today, experts highlight the importance of learning from history. They explain how areas of wartime fascist resistance in Italy remain less susceptible to the far right today – and what that can teach us about today’s world. And why Stalin’s actions in Poland during the war may tell us something about Putin’s approach to Ukraine right now.

Meanwhile, your fridge might be a breeding ground for bacteria – here’s what you can do to improve it.

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