William Herschel was a German-British astronomer who built his own telescopes and used them to discover the planet Uranus, the first planet to be discovered since antiquity, as well as several its moons and the moon and Saturn. He correlated periods of low solar activity to increases in prices of wheat, and made it known that coral is not a plant, among many other things. Most interestingly, he was the first to discover that there is light beyond the visible spectrum, while passing sunlight through a prism and holding a thermometer just beyond the red end of the spectrum.