California Nebula: This is a huge hydrogen cloud in the constellation of Perseus visible only as a brighter shade in very clear and dark nights. It seems to resemble the state of California. Some very bright stars, predominantly the one close to the center part of the image make the dense dust and hydrogen clouds shine in the emission lines of several elements.

The image was composed from frames taken with four different narrow band filters letting pass only the H-alpha line of hydrogen, the [OIII] line of oxygen, the [SII] line uf sulfur and the H-beta line of hydrogen.