simeis 57, propeller nebula,

Simeis 57 - The Propeller Nebula


Ha 135

Tele Vue NP 127fli

ASA DDM 60 Pro

FLI ML 16200


Constellation Cygnus

Ra 20:15.60.00

Dec +43:40:00.0


Simeis 57 (also known as HS 191 and C 191; Gaze & Shajn 1951, 1955) is a high surface-brightness nebula in the constellation Cygnus, about two degrees north of the large nebula IC 1318a. It is a prominent object on the Palomar Sky Survey images, not least because of its peculiar S-shape, reminiscent of a garden sprinkler. Various parts of the complex nebula are listed separately in the catalogue of optically visible HII regions in the Cygnus X region by Dickel et al. (1969; hereafter DWB). The southern arm is included as DWB 111, the northern arm as DWB 119.