Jacco van Loon: Mysterious matter in interstellar space

The light from stars is intercepted by molecules in deep space but we do not know what the majority of these particles are. They appear as absorption features in the spectra of stars and are therefore called “Diffuse Interstellar Bands”. They were first discovered by  Mary Lea Heger around 1920, a find, I would argue, more significant than the tomb of Tutankhamun. I will tell you this century-old detective story. How we are using powerful telescopes to tease out new clues, and why it all matters. Be prepared for audience participation – to solve the mystery, you have to become the mystery!