A bumper edition

Japanese pedestrians have been forcefully colliding with each other in a spate of butsukari otoko – or ‘bumping man’ – incidents and the Unexpected Elements team has been inspired to investigate some bumpy science.First, what does your heart desire? Well, at a cellular level, the perfect match! We hear how your heart is built by cells going speed dating. Then, we discuss how birds avoid in-flock collisions, and we learn all about mesmerising murmurations.Next, we’re joined by science journalist and author Robin George Andrews, who tells us about NASA’s mission to avoid a city-killing disaster by bumping into an asteroid before it can bump into us.Also, a colourful question about migraines, a surprising new treatment for them, and the scientists who took antimatter for a test drive.All that, plus many more Unexpected Elements.Presenter: Marnie Chesterton Producers: Sophie Ormiston, with Ella Hubber, Katie Tomsett, Imy Harper and Lucy Davies