The Horsehead Nebula, Barnard 33 (B33), is one of the most famous deep-sky objects in the heavens. Located in Orion roughly 1,375 light years away, it comprises a region of dark gas and dust backlit by the emission nebula IC 434. The region is powered by the energy from the star Sigma Orionis (σ Orionis), which is above the frame of this shot. The striations in the red or pinkish material of IC 434 may be due to magnetic fields that formed in the gas cloud.

The relatively dense nature of the dark cloud of B33 is ripe for star-forming activity. This may be encouraged, yet also limited by the presence of Sigma Orionis. Its radiation can cause gas to compress in the nebula, triggering such star formation. But then the formation of these stars can disrupt this process and thus limit star formation.

This iconic object is what originally got me interested in astronomy back in 1965 in first grade. We used to get these Nelson Doubleday Science Service booklets for free every three months in grade school. The subject matter ranged from archaeology to sociology. But one of the first booklets we got was called “Universe.”

It contained this picture of the Horsehead taken on an emulsion plate by Milton Humason on February 7, 1951 with the 200-inch Hale Telescope on Mount Palomar. I was mesmerized:

 I was amazed that such an intricate and beautiful object was passing right over my head every night.

I hope I've done the original picture honor here. This is LRGB only—no steenkin' Ha. As usual, you have to have been born by at least the second administration of Dwight Eisenhower to get my attempts at humor.