Artwork of the light path from the GRB

Before light from the gamma-ray burst arrives at the Earth for astronomers to study, it passes through interstellar gas in its host galaxy (close-up view, left), and intergalactic gas between the distant galaxy and us (wide view, right). This gas absorbs some colors and leaves a signature on the light that can be seen in its spectrum. This “signature” allows scientists to characterize the GRB, its environment, and the material between us and the distant galaxy. Credit: Gemini Observatory/AURA, artwork by Lynette Cook