
The clouds that form this structure are called " molecular clouds", constituting a phase of the interstellar medium which is cold and dense enough for molecules to form, particularly molecular hydrogen (H 2).

The region forms part of the Great Rift, the nearby dark cloud of cosmic dust that obscures the middle of the galactic plane of the Milky Way, looking inwards and towards its other radial sectors. The Serpens–Aquila Rift (also known as the Aquila Rift) is a region of the sky in the constellations Aquila, Serpens Cauda, and eastern Ophiuchus containing dark interstellar clouds. It is part of the Great Rift which can be seen bisecting the swath of star light seen in the galactic plane.

In this image of the Milky Way, the Aquila Rift is the dark patch right of center.
