Sh2-204 is a compact emission nebula in Camelopardalis, glowing primarily in hydrogen alpha and sculpted by the intense radiation of nearby massive stars. Its curved, asymmetric form is created by the pressure of stellar winds sweeping through the cloud, compressing the gas into this distinctive shrimp-like arc. The region sits along the outer Milky Way and is often overlooked because of its faint surface brightness, but long integrations reveal complex filaments and a surprisingly rich ionization front.

The blue accents often seen in images come from oxygen emission that outlines parts of the shock front, while the deeper reds trace hydrogen heated by ultraviolet light. Sh2-204 is part of a larger network of clouds in the Camelopardalis OB1 association, an area filled with young, energetic stars that continue to shape the surrounding gas. Capturing it cleanly requires both dark skies and patience, but when it comes together, the structure is one of the more unusual forms in the northern sky.