Why don't we get invisible animals on land? What's at the centre of a gas giant? Did we really land on the moon? Four special guests join Chris Smith to shoot the scientific breeze in this month's question and answer spectacular.

Jacek Mokrosiński studies the genetic make-up of people who are severely obese. His research into the molecular pathways of ‘extremes’ will contribute to treatments for a stigmatised condition. Mokrosiński is also involved in LGBT initiatives.