The section depicted by the "Gulf of Mexico" in the image below is more commonly referred to as "The Great Cygnus Rift" and represents the starting point of dust clouds which continue onto Aquila and Ophiuchus and bisect our Milky Way in half when viewed edge-on, for the dust obscures starlight and yields the observer darkened lanes or nebulae stretching for one thousand light-years across. These dark nebulae expand in size as one moves away from Cygnus and progresses southwards towards Aquila and Ophiuchus. The Great Cygnus Rift, also known as the Northern Coalsack, is also an area of very active star formation and only two thousand light-years away from the two other major star formation areas in the general vicinity, namely NGC 7000 (North America Nebula) and IC 5070 (Pelican Nebula). Further details at http://www.perseus.gr/Astro-DSO-NGC-7000-Rift.htm .