This illustration depicts a compact merger event that is emitting three multi-messenger signals: photons, neutrinos and gravitational waves. Cosmic rays, made up of high-energy particles, come from other distant sources throughout space and are deflected and neutralized by Earth's atmosphere and magnetic fields. Multi-messenger astronomy aims to combine the information from more than one of these signals to give researchers a deeper understanding of some of the most extreme events in the Universe. NSF–DOE Vera C. Rubin Observatory will soon contribute to this emerging field by using its powerful camera and wide field of view to find faint multi-messenger sources and point other telescopes in the right direction for follow-up observations.