Q&A: Martian sunsets and submerged sloths

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? Astronomer Matt Bothwell, marine biologist Kate Feller, palaeontologist Jason Head and geneticist Diana Alexander join Chris Smith to shoot the scientific breeze in this month's question and answer spectacular. Like this podcast? Please help us by supporting the Naked Scientists