It is already is. This is why Iceland's one of the main producers of bananas. A lot of bananas come from Iceland because it's a centre of geothermal activity. It's an area on the Earth's surface where heat from inside actually heats up things like water, so you get very hot geysers, hot rocks and areas of the earth. You can harness that heat, and in Iceland they use it to power their greenhouses for growing bananas. In other parts of the world as well there is geothermal heat being used to generate energy. In New Zealand, it's already used. The way you do it is you pump water down to where the rocks are hot enough and the water comes up at very high temperatures and very high pressure. You can then either send that water off as a direct distribution or you can pass it through a heat exchanger and then distribute that heat around people's houses, hospitals and places that need energy. It's great for bathing in too. However, this is only used where it's economical and the rocks are close enough to the surface.

There is and they rely on Einstein's theory of relativity to get around the problem with GPS, but not really for everybody because it depends how far the signal has to travel. The only way round it is to provide local time signatures. And they're going to switch off the analogue signals so it's going to cease to be an issue and we'll all be slightly out of time. The thing is, we live in a world where the average person has their watch out by several minutes relative to Greenwich Mean Time, so a fraction of a second disparity on the television is probably not going to affect people's lives if I'm being really honest.

Humans are incredibly visual creatures. We devote over a third of our brain power just to being able to see. That makes us quite similar to dogs, although dogs of course live in less of a visual world and more of a smelly world. A dog's nose is 3000 times more sensitive to smell than a human. When you go to sleep and have a dream, the regions of the brain you use during the day to do various tasks light up if you have a brain scan while dreaming. If you look at people who are dreaming and look at the visual areas of the brain you'll see that they're becoming very active. When you wake people up when they're showing those signs and ask them what was happening, they'll say that they were in a field or walking around and experiencing something. They can give you a pretty graphic description. When you're blind, often what happens is that when you've seen once, the bits of the brain that used to do the seeing have laid down a pretty powerful memory of what's out there in the world around you. You know what colours there are you know what objects look like. When you go to sleep, although there's no direct input from the eyes now, still can generate those images and they're every bit as real as they were when you really were seeing. I have a lot of blind friends that they actually love going to sleep because it reminds them of what seeing is like, and it also reminds them of what colours are like.

It depends on how you define colour-blind. The version of that urban myth that I've heard is that they see in black and white, and that's just not true. If you look at a dog's retina, the thing that turns light into neurochemistry or electrical signals, there are structures in the dog's retina called cones. These are identical to structures in the human retina called cones that can see coloured parts of the visual system. So dogs can definitely see colours. But if you analyse those cones, they paint a very different picture of what dogs see of the world than what humans do. The best description is that dogs are the equivalent of human red-green colour blindness. So they have a spectrum of colours that means they are pretty good at seeing greens, violets and blues, but at the red end of the spectrum they're less good. They probably appreciate it as a slightly different colour, such as yellow. But they're certainly not colour blind.

The heart pumps around fifty times per minute. It pumps about five litres of blood a minute. So if you times that by sixty for the amount of blood in an hour and then times it by 24 for the number of hour in a day, it's about 7500 litres of blood every single day. Blood is about 1 gram per centimetre cubed, which means it's a thousand grams per litre. That means that if you pump 7500 litres in a day, that's 7.5 tonnes of blood pumped around your body every single day.

Well for a start, don't pull your nose hair. You should clip it to avoid infections. It hurts because your nose is very sensitive and has lots of nerves in there. It's a super nerve reaction when it happens.