What is Interferometry?

Interferometry is a technique used by scientists and engineers. Tools called interferometers add together 2 or more waves of light. When they do this, the waves of light interact (or interfere) with each other. This can add the waves together, making them brighter. It can also cancel the waves out. Interference only takes place if the waves come from the same object or have the same frequency. We call these types of wave coherent.

Scientists have 2 ways to think about light: it can be a wave or a particle called a photon. It took a long time to discover that both were true. For some time there had been a debate between supporters of each point of view. Nobody - or everybody - won the argument; light is both wave and particle.

Have you seen colour pictures of nebulae and galaxies? Have you thought about how those pictures were made? Did you know you can make your own with Go Observing and LTImage?