Light and the Spectrum

Saturn's aurora in infrared

Image courtesy of NASA

Saturn's aurora shown in infrared.

Electromagnetic radiation is a key element in understanding our universe. Because of great discoveries in light and the electromagnetic spectrum, astronomers are able to analyze what they can see of space and also what they cannot see by studying the objects through various wavelengths. Gamma rays, for instance, have shorter wavelengths but give off hotter, more intense energy. Radio waves, on the other end of the spectrum, are made of longer wavelengths but the energy emitted is not as hot or intense. By studying the continuous, emission, and absorption spectra of objects, astronomers can discover the composition as well as the distance of objects faraway in space. Astronomers are constantly learning new facts about our universe by studying it in all parts of the electromagnetic spectrum.