A spectrometer is like a special type of camera that is used to see things that we can't normally see with our eyes. It takes light and turns it into information about what the light is made of. It does this by splitting the light into a bunch of different colors, like a rainbow. It looks at each of the different colors and measures how much of that color is in the light. That information can tell us a lot about what the light was made of, like what elements are in it.