The Horsehead Nebula is located just to the south of the star Alnitak and is approximately 1500 light years from Earth. The name comes from shape of its swirling cloud of dark dust and gases which resembles a horse's head when viewed from Earth. Very large telescope images show this very well. The reddish color is from hydrogen gas behind the Horsehead Nebula which is ionized by the nearby bright star Sigma Orionis (source: wikipedia).
The Flame Nebula is an emission nebula is about 900 to 1,500 light-years away. Again, the bright star Alnitak is responsible as it shines energetic ultraviolet light into the Flame. The light knocks electrons away from the clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine (source; wikipedia).
Location: Happy Frog Observatory, Monroe, CT
Date/Time: 12/29/16 and 12/30/16, 11:45 pm
Camera: Canon EOS Rebel T3i(a), Backyard EOS
Telescope: Orion ED80 80mm f/7.5 Apochromatic Refractor Telescope
Focal Length: 600mm
Mount: Orion Sirius EQ-G GoTo Telescope Mount
Filter: Astrodon UV/IR, Astronomik Clip-UHC
Autoguiding: QHY-5L-II-M attached to an Agena 50mm Guide Scope with Helical Focuser
Exposure: 55 x 180 sec (2 hrs 45 min)
Temp: 25 C
Post Processing: Deep Sky Stacker, Photoshop, Lightroom, Astrophotography Tools, StarTools