The California Nebula

The California Nebula lies about 1,000 light years from earth, but that distance isn't enough to stop me from imaging it from my backyard! This nebula is an emission nebula, meaning the gases you see in this image are also responsible for the brightness of the nebula. It's extremely rich in hydrogen, which constitutes virtually all of the gaseous structure that can be seen in this image. It's easy to see how the California Nebula earns its namesake when this image is viewed with a 90º clockwise rotation, where the nebula has a very similar shape as the state of California. It's also about 100 light years across and is responsible for stars forming in the region. This image utilizes an HHO palette, where my hydrogen exposures are assigned to red and green and the oxygen exposures are assigned to blue.