Legend has it that Isaac Newton had the moment of inspiration that would lead to his theory of gravity when, on a warm afternoon, he saw an apple fall from a tree and wondered why it should fall down ...

Gravity used to be the most down-to-earth of ideas, the thing that kept apples falling and planets in line. Now a growing ...

If there's one thing everybody knows about space, it's that there's no gravity once you leave the Earth's atmosphere. We all know that don't we? It's actually not true — and an attempt at a massive ...

Keeping an orbiting satellite in the proper attitude is no mean trick. But there are times when antennas and cameras have to be kept pointing continually at the earth if they are to work effectively, ...