RCW 75 (also known as Gum 48a) is an emission nebula
in the southern constellation of Centaurus, and is
located about 6500 light years from earth. Its red glow
is due to a hydrogen cloud ionized by the open
star cluster Stock 16, also visible in this image.
Notice the arcing blue reflection nebula at the end
of the long "elephant trunk."

Image data:
Telescope: Planewave 17”
Camera: SBIG STXL-11002
Exposure: 26 hours 40 minutes through LRGB and hydrogen-alpha filters
Location: Observatorio El Sauce, Chile