A Ring To It. In the show this time, Dr Fergus Simpson tells us about mapping dark matter using weak gravitational lensing [08:44 - 14:49] and Professor Carlos Frenk talks about exploring the nature of dark matter through simulations [15:00 - 38:21]. Megan summarises the latest astronomy news [00:47 - 08:28] and we find out about the August night sky from Ian Morison and John Field [42:52 - 60:42].