You can and they have tried it. They took a big long wire a couple of kilometres long and hung it from a shuttle. They tried to generate power by moving it through the Earth's magnetic field. The problem is that it's very difficult to manoeuvre a 2-kilometre wire through space. If you started a wave through it, there's no air to dampen down the vibrations. You also get some complex interactions between the magnetic field and the wire. The other problem is that it takes the energy out of the orbit, so the satellite will come out of orbit quicker. This is ok for a space station because it gets pushed regularly, but it's not ideal for a satellite that wants to stay up there for a long time. So actually it's a lot easier to use a solar panel.

String theory is a way of looking at the world to try and work out what we're made of. You may have heard that we're all made of atoms, and atoms in turn are all made of other little bits such as electrons, neutrons and protons. If you break it down even further, things like neutrons and protons and stuff are made up of even tinier particles called quarks and leptons. All these different particles are what makes up stuff. There are different forces that can act on stuff to make things move and stick together. These are gravity, electromagnetic force and the weak and strong nuclear forces. Sounds a bit Jedi to me! These help to stick stuff together. We have a standard model for how you explain stuff, which is that quarks and things stick together and protons and neutrons stick together etc. But you can't really explain how gravity actually works using this kind of model. So some very clever maths bods have been trying to work out a way of explaining how gravity works using the bits that we have. They've come up with string theory, which says that all these tiny bits of stuff are actually like bits of string that wobble around in lots of different ways. It depends how you're seeing that particular waving string as to what you see. So if you see it waving in one sort of way you see a lepton, and if you see it in another way you see an electron. So everything is basically little bits of waving string and this can apparently explain gravity. You can find out more at www.superstringtheory.com. However, no-one has found any evidence that this is the case. All the things it predicts happen at such high energies that no-one has been able to look at them yet.

They did do it a fair amount. The Moche are actually one of the most epic examples of this sort of thing that you can find in the world ever. Some cultures did this to a certain extent and had sacrifices in a more modest way. The Incas used to bury children on mountain tops for example. But the Moche were really really sanguineous. They had a little tiny area on the coast of Peru and they hacked it out of virtually nothing so it was very small with lots of canals and agriculture. The society was very rigid and they would go out to fight other tribes and nick all their land and so on. They would then ritually decapitate all of the captive men. They sometimes kept some of the women, but not very often. They would cut off their arms and remove bones from their arms while they were still alive. They would smash bits of them off and then throw then off these cliffs into an enormous pit and leave them there for the vultures to eat. They were pretty nasty! They even had a deity called the decapitator god, which had a giant eagle-like head and a nasty blade in his hand. He would go around decapitating all the captors.

The myth or story of Atlantis is based upon a gigantic slip of land into the Atlantic or possibly Mediterranean, which contained a civilisation that was privy to lots of information that we no longer have. So yes, there is evidence of slip in the Iron Age in the Mediterranean and particularly around Turkey, but when it comes down to whether we've lost information which mankind would really benefit from today is a bit more difficult to demonstrate unfortunately. As for the planets, people have interpreted it like that but most of the cave paintings are so bizarre that no-one really knows what they mean. They have animals, which is fair enough, and then they also have lots of demonic creatures. You then have people with duck's heads and so on. So the planet thing is one possibility but it's a rather slim one unfortunately.

Oil is the rotten remains of trees and other vegetation. If you go back to the time of the oil and certainly the coal-bearing strata we have in the British Isles, the British Isles wouldn't have looked like it did today. It was significantly further south towards the equator and therefore had a much more tropical climate. The nature of the vegetation would have been similar but not identical to perhaps modern tropical rainforests. As they died and fell down, they were buried over long periods of time, compressed and ultimately that forms oil. Quite a lot of oil is made from algae in the sea. Algae gets cooked when it's buried deeply. That gives off oil which floats up nearer to the surface.

If the Earth suddenly didn't have any gravity any more, I guess that the first thing to happen would be its effect on the atmosphere. At the moment, the atmosphere is being compressed by its own weight and squashed down onto the Earth. The first thing that would happen is that the atmosphere would expand very quickly and fly out everywhere. That might blow you up into space. If it wasn't for that, there would be any reason for you to be thrown away from the Earth. You'd just sit there and slowly get pushes around. So you'd have a huge explosion with all the atmosphere disappearing, and this could possibly blow you up into the air.

It's possibly a dew pond. These have been constructed through much of the South Downs and counties in the south of England. They're built on the top of hills so when the warm air rises, it condenses. The ponds are lined with clay and the clay cools down. This also helps when the air sinks to leave moisture behind. This forms a pond which farmers use to give water to their animals.