December 3, 2024

Archives for January 19, 2021

M31 – Spiral Galaxy in Andromeda

M31 – Spiral Galaxy in Andromeda – Celestron Comet Catcher 5.5” f/3.6 Schmidt Newtonian

Telescope: Celestron Comet Catcher 5.5” f/3.6 Schmidt Newtonian, Orion Atlas EQ-G

Camera: ZWO ASI294MC Pro, 0C; Gain: 200

Filter: Hutech IDAS LPS P2

Guide scope: Williams Optics 50mm, Meade DSI Pro III, PHD

Exposure: 47x120sec saved as FITS

Darks: 32x120sec saved as FITS

Flats: 32×0.25sec Tee shirt flats taken at dusk

Average Light Pollution: Red zone, good transparency

Lensed Sky Quality Meter: 18.7 mag/arc-sec^2

Stacking: Mean with a 2-sigma clip.

White Balance: Nebulosity Automatic

Software: Nebulosity, Deep Sky Stacker, Photoshop

M31 is an iconic spiral in the constellation of Andromeda. Under dark skies it is easily visible to the naked eye and from urban skies it is an easy object for binoculars and small telescopes. At a distance of some 2 million light years, it is the farthest object easily visible to the naked eye. M31 also has several satellite galaxies, two of which are visible here. M32 is about as bright as the core of M31 and is located at the bottom center of this field. To the upper right is the much fainter M110. It is easy to be disappointed with the visual appearance of M31 since it is often shown in highly processed images such as the one I give here. However, the true appearance is quite beautiful in its own way. The core is relatively bright and almost stellar, surrounded by a soft luminous glow that I always think of as pearl. This gradually fades into the background sky.