Lynds Dark Nebula 904 is a large dark nebula known as the Northern Coal Sack. It has an approximate size of 3 x 3 degrees.

It lies between NGC 7000, the North America Nebula, at left, and IC 1318, around Sadr (Gamma Cygni), at lower right.

LDN 904 lies in Cygnus and marks the beginning of the Great Rift in the Milky Way. The Rift runs all the way through Cygnus into Vulpecula, Scutum, Serpens, Ophiuchus, Sagittarius and finally Centaurus.

North is to the top in the above image.

LDN 904 Catalogs: LDN 904 Common Name: Northern Coal Sack Object Type: Dark Nebula Size: 3° x 3° Constellation: Cygnus Image Field Centered At: RA: 20h 34m 18s Dec: +42° 51' 06"