NGC 7538 is a small (8'x7') emission nebula, visible in the constellation of Cepheus, not far from the more well-known Bubble Nebula. NGC 7538 is one of the easiest regions of intense star formation to observe, thanks to the fact that it does not appear obscured by dark clouds and dust.
Given its distance of about 9100 light years it is found on the branch of the Milky Way called Perseus Arm, in correspondence with the brilliant association OB Cas OB2, together with other nebulae such as Sh2-157 and Sh2-161.
Technical data Optic GSO RC12 Truss - Aperture 304mm, focal lenght 2432mm, f/8 Mount 10Micron GM2000 HPSII Camera Moravian G3-16200 with external filter wheel 7 positions Filters Astrodon Gen2 E-Serie Tru-Balance 50mm unmounted RGB, Astrodon 50mm narrowband filters Ha 5nm and OIII 5nm Guiding system OAG Moravian M68 with guide camera Moravian G1-0301 Exposure details R 22x300" bin2 -25C G 20x300" bin2 -25C B 22x300" bin2 -25C
Ha 29x600" bin2 -25C
OIII 18x600" bin2 -25C Total integration 13h10' Acquisition Voyager, PHD2 Processing Pixinsight 1.8, Photoshop CS5 SQM-L 20.67 Location Promiod (Aosta Valley, Italy), own remote observatory Date 26/27 October 2021, 5/6 November 2021