Dr Karl Podcast

Why do some people get itchy legs when they exercise? Plus: what causes some people's cheeks to swell and tingle while eating cheese? And why is bellybutton fluff always blue?

Why do some people see thousands of tiny spots when they look up at the sky or a bright light? What causes a white rainbow? And is there any science to explain ghosts?

What's it like to live in space for 183 days? NASA astronaut Dr Gregory Chamitoff joins Dr Karl to answer all your space questions.

Why do some people work harder at the gym when they listen to a favourite tune? Plus: why does your stomach rumble when you are hungry? And why do your hands tingle after an orgasm?

Why does a bruised apple taste differently to an unbruised one? Plus: is it possible to evaluate the capacity of the brain in gigabytes? And why does caffeine make you feel sick in the stomach?

Why doesn't the skin around nipples get sunburnt? Would global warming interrupt the Atlantic conveyer current and cause an ice age in the northern hemisphere?

Why does it feel unusual when walking on a stationary escalator? Plus: why did the recent Chilean volcano ash cloud travel in the opposite direction to the prevailing winds? And why are oranges orange?