We live on a huge sphere that is spinning and moving through space. All around us - huge distances away - there are other spheres. The most important to us is our Sun, which is also our nearest star. The closest to us is our own satellite, the Moon.

We rotate once every day, bringing us into the Sun's light and the daytime, once every 24 hours. We orbit the Sun, travelling right round it and through all the seasons, once every year.

The Moon orbits us every month. Because it also rotates every month, the same side stays facing us. It appears to change in shape because it is lit by the Sun and the size of its shadow changes.