Astronomy is based on the collection and analysis of the information that is present in the light we receive in all wavelengths. Telescopes like ALMA in radio, JWST in the IR, Gran Telescopio de Canarias in the optical spectrum, and XMM-Newton, Chandra and ATHENA in X-rays obtain now and in the future spectra with a resolution never achieved before. The observed spectrum depends of a number of coupled thermal atomic and molecular processes in the emitting gas. Cloudy is a spectral photoionization code that solves these problems simultaneously and self-consistently. I will talk about different challenges in astronomy and how we can use Cloudy to contribute to their solution from an atomic physics point of view.