Coloured Bruises, Colliding Bullets and Collapsing Bridges

This week on Ask the Naked Scientists we find out why a beating turns us blue, what would happen in a fight between bullets and how hanging from the air is considered safe in the form of a suspension bridge. We also find out about an environmentally-friendly method of cremation, whether it's possible for humans to survive on Mars and what the term horse-power actually means. All that and even more of your questions answered on this weeks podcast.