Image Credit : Bray Falls
With the name of NGC 1499 a visible emission nebula is known that can be seen in the constellation of Perseus. Due to its peculiar shape it is also called the California Nebula, since it is quite reminiscent of the outline of this state of North America.
The California Nebula was discovered by the American astronomer Edward Barnard in 1885. It is located in the Orion arm, relatively close to Earth, about 1,000 light-years away. In fact, our Sun, which is also in the Orion arm of the Milky Way, is located just over 1,500 light-years from the California Nebula.
The brightness of the California Nebula is due to the intense radiation emitted by a class O star called Xi Persei, which is the brightest that can be seen in the image.
The California Nebula is 2.5 ° C long, but its surface brightness is low. For this reason, the best way to appreciate it in all its splendor is through long exposure photographs. It can only be seen with the naked eye on nights that are very dark.
The red color shown by the California Nebula is due to hydrogen alpha. This reddish light comes from hydrogen atoms in which an excited electron in the atom returns to a low energy level, releasing a photon of that wavelength.