The James Webb Space Telescope has revealed the clearest ever view of the stunning Cassiopeia A supernova, complete with a weird feature called 'the green monster'. Professor Dan Milisavljevic, an astronomer at Purdue University, tells us all about his research into this space-based beauty. Professor Tamara Davis from the University of Queensland has been turning her eye to far more distant supernovas, and explains how they have given us new insight into the Universe's expansion. Moving on to human history, William Barrie from the University of Cambridge tells us about a new study that explores the reason for high levels of multiple sclerosis in northern Europe. And going further back in time, researcher Ethan Mooney has studied a sample of fossilised skin, which may be the oldest ever discovered. Presenter: Roland Pease Producer: Alice Lipscombe-Southwell Editor: Martin Smith Production co-ordinator: Jana Bennett-Holesworth (Photo: Cassiopeia A Supernova. Credit: Nasa, ESA, CSA, STScI, Danny Milisavljevic, Purdue University, Ilse De Looze, UGent, Tea Temim, Princeton University)