Given that photons are massless, how do solar sails get pushed along by light? We explore the reasoning in this Question of the Week! Plus, we ask why wet dogs always seem to smell so appalling. Like this podcast? Please help us by <a href="https://www.thenakedscientists.com/donate">supporting the Naked Scientists</a>

Why do wet dogs smell?

Each week we set out to solve one of the world's weirdest, wackiest, funniest and funkiest scientific puzzles. And along with the answer there's a brand new question to think about for next time...