The Elephant’s Trunk nebula is a concentration of interstellar gas and dust in the star cluster IC 1396 – an ionized gas region located in the constellation Cepheus about 2,400 light years away from Earth. The piece of the nebula shown here is the dark, dense globule IC 1396A; it is commonly called the Elephant’s Trunk nebula because of its appearance at visible light wavelengths, where there is a dark patch with a bright, sinuous rim. The bright rim is the surface of the dense cloud that is being illuminated and ionized by a very bright, massive star that is just to the west of IC 1396A. (In the Figure above, the massive star is just to the left of the edge of the image.) The entire IC 1396 region is ionized by the massive star, except for dense globules that can protect themselves from the star’s harsh ultraviolet rays.
Optics/mount: 12″ACF 2.7m AP-Reduzer Alt-5
Camera/filters: Atik 11002 Astrodon LRGB HA5nm
exposure: 10×600 Lum 6×600 RGB all 1xbin