The Flame Nebula (NGC 2024) is in the Constellation Orion and it is about 900 to 1,500 light years away. The bright star Alnitak, the easternmost star in the Belt of Orion, shines energetic ultraviolet light into the Flame and this knocks electrons away from the great clouds of hydrogen gas that reside there.

Much of the glow results when the electrons and ionized hydrogen recombine. Additional dark gas and dust lies in front of the bright part of the nebula and this is what causes the dark network that appears in the center of the glowing gas. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the the Horsehead Nebula.

The Horsehead Nebula is a famous diffuse dark nebula found in the Orion Molecular Cloud Complex in the constellation Orion.

It is a dark cloud composed of dust and gas where star formation is taking place. The nebula is also known as Barnard 33, and is located in the emission nebula IC 434. The Horsehead Nebula is approximately 1,500 light years distant from Earth.

The Horsehead Nebula is one of the most easily identifiable nebulae in the sky as its shape resembles that of a horse’s head and neck when observed from Earth. The swirling clouds of gas and dark dust are lit by a pinkish glow of hydrogen gas located behind the nebula and ionized by the nearby bright star Sigma Orionis. Sigma Orionis, which is in fact a five-star system, illuminates the entire region.

The nebula formed from a collapse of an interstellar cloud of material and appears dark mainly because of the thick dust in the neighbouring area, with the bright spots at the base marking hidden protostars, newly formed or forming young stars.

The Horsehead can only be seen because its obscuring dust is silhouetted against the brighter nebula IC 434. The nebulous region that forms the horse’s head is just part of a larger dust cloud.