| Emission nebula | |
|---|---|
 | |
| Observation data: J2000.0epoch | |
| Right ascension | 04h 03m 18.00s |
| Declination | +36° 25′ 18.0″ |
| Distance | 1300±160[1] ly (410±50 pc) |
| Apparent magnitude (V) | 6.0 |
| Apparent dimensions (V) | 2.5° long |
| Constellation | Perseus |
| Physical characteristics | |
| Radius | 22[2] ly |
| Designations | NGC 1499,Sharpless 220 |
| See also:Lists of nebulae | |
TheCalifornia Nebula (Also knownNGC 1499 orSh2-220) is anemission nebula located in the constellationPerseus. Its name comes from its resemblance to the outline of the U.S. State ofCalifornia in long exposure photographs.
By coincidence, the California Nebula transits in thezenith in central California as the latitude matches the declination of the object.
NGC 1499 is almost 2.5° long on the sky and, because of its very lowsurface brightness, it is extremely difficult to observe visually. It can be observed with aHα filter (isolates the Hα line at 656 nm) or Hβ filter (isolates the Hβ line at 486 nm) in a rich-fieldtelescope under dark skies.[3] It lies at a distance of about 1,000light years fromEarth. Its fluorescence is due to excitation of the Hβ line in the nebula by the nearby prodigiously energetic O7 star,Xi Persei (also known asMenkib).[4]
The California Nebula was discovered byE. E. Barnard in 1884.
