[4] The nebula was discovered by Scottish astronomer Williamina Fleming in 1888 on a photographic plate taken at the Harvard College Observatory.

4′, on nebulous strip extending south from ζ Orionis", cataloguing the dark nebula as Barnard 33.

Magnetic fields channel the gases, leaving the nebula into streams, shown as foreground streaks against the background glow.

[8] A glowing strip of hydrogen gas marks the edge of the enormous cloud, and the densities of nearby stars are noticeably different on either side.

[11] The visible dark nebula emerging from the gaseous complex is an active site of the formation of "low-mass" stars.