The Horsehead Nebula, Barnard 33
The Horsehead Nebula, Barnard 33. is a dark cloud of obscuring gas and dust which lies in front of the extended pink glow of the IC 434 emission nebula. Radiation from Sigma Orionis, the star to the left of the Horshead and Alnitak, the star below the nebula is exciting the gas of IC 434, causing the soft pink glow.
Just to the right of Alnitak, is a yellowish reflection nebula with dark dust lanes - NGC 2024, the Flame Nebula.
Just below the Horsehead Nebula, at about the 4 o'clock position is the bright reflection nebula, NGC 2023.
| Types of Nebulae | |
| Type | Composition |
| Emission Nebulae | Heated gas which generates light |
| Reflection Nebulae | Clouds of gas that reflect the light of nearby or embedded stars |
| Absorbption Nebulae | Clouds of gas that block light from more distant objects |
Note: The circles and spikes around Mintaka and Sigma Orionis are diffraction artifacts caused by the optics of the telescope.
This image image from the UK Schmidt telescope
is approximately 1.2° wide and 1.8° high.