Atomic spectra refer to the unique patterns of light emitted or absorbed by atoms when they transition between energy levels. Each element has a distinct set of energy levels, resulting in specific wavelengths of light that can be observed as lines in a spectrum. This phenomenon occurs when electrons move between these levels, releasing or absorbing energy in the form of photons. Scientists use spectroscopy to analyze atomic spectra, which helps identify the composition of substances. By studying these spectra, researchers can determine the presence of elements in stars, gases, and other materials, providing valuable insights into the universe's structure and behavior.