In the mid-1660s, Isaac Newton bought a pair of prisms at a fair near Cambridge, which were to be the basis of a series of experiments that would unlock a secret that had occupied scientists for centuries - the nature of light itself.

To explain what he had done, Newton created a diagram. It is called The Crucial Experiment and is a pivotal image in scientific history, a graphic moment when the ancient world was overturned by modern science. Newton demonstrated that white light is not pure, but made up of a number of different colours, the colours of the rainbow.

Newton's ideas transformed our knowledge of what we see and how we see, and the prism and its refracted colours became a captivating image. From fibre-optics to the cover of Pink Floyd's Dark Side of the Moon album, Newton's work went on to influence centuries of science and art.

A look at the Pioneer Plaque, which was installed on the unmanned space probe Pioneer 10 to communicate facts about Earth and its inhabitants to potential life on other planets after its launch from Cape Canaveral in March 1972. The panel was engraved with graphic images and mathematical symbols, showing the location of its origin in the solar system and controversial naked figures of human beings.