Spectroscopy is a way of analyzing light by splitting it into a rainbow of colors called a spectrum. Studying the spectrum closely, scientists can see dark gaps in the colors. Those gaps help determine which chemical elements make up an object. The Hubble Space Telescope (and soon the James Webb Space Telescope) uses spectrographic instruments to study distant objects in space and determine the compositions of galaxies, stars, and planets. Credit: J. Olmsted (STScI) | NASA's James Webb Space Tel