One of the most well known deep sky objects, by name, is the Horsehead Nebula (centre). Situated in the constellation of Orion and located near the bright blue star Alnitak (centre-left), the Horsehead Nebula is a dark nebula which just happens to be the same shape as the familiar horsehead shape (centre image). The horsehead shape is formed from a dark non-luminous nebula cloud (known as Barnard 33) that silhouettes itself against the red glow of the background emission nebula IC 434. Just below and left of the Horsehead nebula is the blue reflection nebula NGC 2023 and further below is another blue reflection nebula IC 435. The large yellowish-brown nebula below the bright star Alnitak is called the Flame Nebula (also NGC 2024). At far left are IC 431 and below is IC 432. Alnitak is measured by the Hipparcos satellite to be 817 light years distance and the Horsehead Nebula is thought to be about 1,500 light years distance.

Image	Horsehead Nebula Region 20080308
Telescope	William Optics 110mm f/5.9 APO Refractor telescope, Observatory mounted Losmandy Gemini G-11 equatorial mount.
Guiding	Autoguided with SBIG 402 on 4.5-inch f/9 guidescope using CCDOps.
Camera	Cooled Canon EOS 350D Digital - Hα enabled (modified).
Exposures	10 x 6-minute exposures @ ISO 400.
Total Exposure time	60-minutes.
Filter/equipment	Baader Coma Corrector. Astronomik 2" CLS Filter.
Processing	Darks, bias and flat-fielded with ImagesPlus, post processing in Photoshop and Noiseware.
Notes	David Houghs cooled Canon 400D on loan.