The distance to the nebula is not known with certainty, but it probably lies some 2,000 to 5,000 light years from the Sun. This means that the entire sprawling region is at least a hundred light years across, and may, depending on its true distance, approach three hundred light years from side to side. It has a mottled appearance, with bright pink-orange areas of ionised hydrogen being obscured in places by a tracery of dark dust clouds and lanes.
A view of the central regions of the extensive Sadr Region. The brightstar to the east (left) of centre in this view is Sadr itself, the foreground star from which the region takes its name. Visible within the nebula are two young open clusters, Collinder 420 (to the northeast of Sadr) and Collinder 419 (to the northwest). Imagery provided by Aladin sky atlas
Three brighter areas of the Sadr Region stand out from the main mass, and these are given individual designations. IC 1318A forms a distinct northern lobe in the north of the Region, while IC 1318B and IC 1318C lie to the south, closer to the starSadr in the sky. IC 1318B and IC 1318C form a nearly symmetrical pattern divided by a dark lane, and are sometimes jointly known as the Butterfly Nebula (not to be confused with C69, the Bug Nebula in Scorpius, which is also sometimes known as the 'Butterfly Nebula').