Could we really live on Mars?

Collagen powders, gummies and pills have boomed in popularity in recent years boosted by claims that they smooth wrinkles, promote glossy hair and help with joint pain. Amid the noise it can be hard to figure out whether there’s any actual science behind the promise of looking younger for longer. Luckily Dr Xand van Tulleken has spent the past three years writing Make me well: a quest to understand the confusing world of wellness, and his chapter on collagen dives deep into the evidence. He tells Madeleine Finlay what collagen does in the body, how we can get it without splashing out on expensive supplements, and why getting to the truth behind wellness claims can be so hard. Help support our independent journalism at theguardian.com/sciencepod

In this episode of Science Weekly, recorded in front of an audience at the London podcast festival on 3 September, Ian Sample hears from Michael Safi, the host of the Guardian’s chart-topping podcast about artificial intelligence, Black Box. In series two, Black Box: the chatbots, Michael meets people who have become convinced they have made scientific breakthroughs, cured diseases or invented new technologies using AI chatbots. Ian, Michael and Science Weekly’s co-host Madeleine Finlay explore the phenomenon labelled ‘AI psychosis’ and ask what it reveals about a technology now used by more than a billion people. Help support our independent journalism at theguardian.com/sciencepod

For decades physicists have been puzzling over the enigma of dark matter. We think it makes up 85% of the matter in the universe, but the mysterious substance cannot be seen or detected, and we know about it mainly through observations of the gravitational effects it has on other things. But now scientists believe they may be a step closer to detecting it. Science editor Ian Sample explains to Madeleine Finlay why, if confirmed, the finding could completely transform our understanding of the universe. And Dr Samuel Eriksen, senior research associate at the University of Bristol, and first author of the research paper, explains how the finding has been received in the physics community. Help support our independent journalism at theguardian.com/sciencepod

Who’s more likely to steal sweets from a child? According to science, it’s the rich. A study seemingly confirming our suspicions about the moral behaviour of the wealthy was one of the winners of the 2026 Ig Nobel prizes, which honour research that makes you laugh and then think. Science editor Ian Sample tells Madeleine Finlay what the researchers think could be behind the phenomenon, and they explore some of the other awards, including one for a surprising quality we look for in our friends and another for a biomechanical definition of kissing. Help support our independent journalism at theguardian.com/sciencepod

From the Guardian Investigates team: Across the world, hundreds of people have come to believe they have made extraordinary scientific discoveries with AI chatbots such as ChatGPT, Claude and Gemini. Others say their AI has ‘awakened’ or is leading them to a higher spiritual realm. The Guardian journalist Michael Safi begins investigating a phenomenon labelled ‘AI psychosis’, travelling to the US to meet two people who have been on weird journeys with their chatbots. Help support our independent journalism at theguardian.com/sciencepod