The Naked Scientists are joined by biologist Kate Feller, physicist Jess Wade, biochemist Andy Holding and Space Boffin Richard Hollingham, to field your science questions. This week, find out what happens to muscles in space, how to rid a car of flatulence, and whether any animals can become invisible. Plus, cyber security expert Paul Harris talks to Chris Smith about the recent cyber attacks - what happened, and how we can protect ourselves.