The Horsehead nebula (B33), to the left the bright star is Alnitak and below that is The Flame Nebula (NGC 2024). Alnitak is the eastern most of the three stars to make up Orion’s Belt.
For reference the other two are above and to the left of this frame. The Orion Nebula is to the left out of view. There are a few other emission nebula in this photo, like IC 435, NGC 2023, IC 431, IC 432 among others.
B33 is 1500 light years away and is actually dust blocking the light from the Ionized hydrogen gas behind it. That’s called a dark nebula.
This is made from 274 45 second exposures at f4.5 and ISO 100 with a Nikon 500 f4.
I stacked 274 light, 57 dark, 92 flat, and 141 bias frames to make this image, for a total integrated exposure of just short of 3.5 hours.
Images stacked with Deep Sky Stacker, and post processed in StarTools