California Nebula
The California Nebula is an emission nebula located in the constellation Perseus. It is so named because it appears to resemble the outline of the US State of California on long exposure photographs. It is almost 2.5° long on the sky and, because of its very low surface brightness, it is extremely difficult to observe visually. It can be observed with a Hβ filter in a rich-field telescope under dark skies. It lies at a distance of about 1,000 light years from Earth. Its fluorescence is due to excitation of the Hβ line in the nebula by the nearby prodigiously energetic O7 star, Xi Persei.
The California Nebula was discovered by E. E. Barnard in 1884.
By coincidence, the California Nebula transits in the zenith in central California as the latitude matches the declination of the object.Gallery
