Observation by Nick James: M31 mosaic

Uploaded by

Nick James


Nick James


2020 Sep 05 - 19:30


2020 Sep 06 - 09:28


The Andromeda Galaxy (M31)

Planetarium overlay



Field centre

RA: 00h42m
Dec: +41°19'
Position angle: -0°00'

Field size

1°42' × 1°51'

  • Celestron HD11 + FLI6303

12 panels of 2x120s


Chelmsford, UK

Target name



M31 mosaic

About this image

I've been playing around with automatically generating mosaics. This is last night's effort on M31. My C11 system has a FoV of 34x22 arcmin  (Celestron HD11 and a KAF-6303 CCD). The telescope is scripted to take the individual panels, in this case 2 exposures of 120s for each of the 15 panels. The images are then calibrated and background normalised using my normal pipeline, plate solved using a local version of astrometry.net and combined into a mosaic using swarp. There is no human intervention in this. The background normalisation isn't brilliant but the general process works quite well giving something like 3 square degrees of coverage to mag 19.5 in an hour. Not quite LSST though!

The full resolution version is here.

Files associated with this observation
Like this image
Copyright of all images and other observations submitted to the BAA remains with the owner of the work. Reproduction of work by third parties is expressly forbidden without the consent of the copyright holder. By submitting images to this online gallery, you grant the BAA permission to reproduce them in any of our publications.