Despina is a tiny moon of Neptune. A mere 148 kilometers across, diminutive Despina was discovered in 1989, in images from the Voyager 2 spacecraft taken during its encounter with the solar system's most distant gas giant planet. But looking through the Voyager 2 data 20 years later, amateur image processor and philosophy professor Ted Stryk discovered something no one had recognized before — images that show the shadow of Despina in transit across Neptune's blue cloud tops.
Einstein realised that the speed of light was one of the defining measures of the Universe. Remember E=mc2, the beautiful little formula that wrapped up the theory of relativity? Well 'c' is the speed of light. And you can measure it. All you need is a microwave, a ruler and a bar of chocolate (and maybe a calculator).