The Andromeda Galaxy (M31) is a majestic spiral island and the largest neighbor to our own Milky Way, situated approximately 2.5 million light-years away. Spanning over 200,000 light-years across, it contains an estimated one trillion stars, double the population of our galaxy and bound together in a breathtaking display of cosmic architecture. In a wide-field view, its brilliant, aging yellow core provides a stark contrast to the sprawling spiral arms, where dark dust lanes weave through nurseries of hot, young blue stars. It is the most distant object visible to the naked eye, appearing as a faint, ghostly smudge in the constellation Andromeda, yet it represents the future of our local cosmos as it draws ever closer to a grand galactic merger with the Milky Way.
M31 Andromeda Galaxy
The original image data for this observation was not captured by me. I processed publicly available data to practice my image processing skills, resulting in this final image.
Fun Facts
- The Galactic Collision: Andromeda is currently heading toward the Milky Way at 110 kilometers per second (68 miles per second). In about 4 billion years, the two will collide and merge to create a new, giant elliptical galaxy.
- A Massive Scale: If Andromeda were bright enough for our eyes to see its full extent in the night sky, it would appear six times wider than the full moon.
- The Ancient Messenger: The photons captured in this image left Andromeda 2.5 million years ago, back when our Australopithecus ancestors were first beginning to walk the Earth.
- The Black Hole Heart: At its very center lies a massive black hole with a mass equivalent to 140 million suns, surrounded by a unique double-star cluster that gives the core its intense, concentrated glow.
- A Family of Galaxies: The image captures its two most famous satellite galaxies, M32 and M110; these are smaller "dwarf" galaxies trapped in Andromeda's massive gravitational pull, slowly being stripped of their stars over eons.
Processing Notes
This is one of my first image processing attempts, based on a raw image provided by SeeStar for a competition they're running to promote their new smart telescope the S30 Pro, which is the one I have on pre-order!
I used Siril for this one, and used the Veralux suite of scripts to remove the background gradient (an effect of light pollution), de-noise, some updates to the colour curves and saturation for the central galaxy and dust lanes. I also did some star removal as this area of the sky shows very crowded when capturing such a wide field object.
I'm pleased with the result, despite blowing out the core a little. And there's definately some colour noise I don't like. But this is a learning experience. It's a good indicator of what I might be able to capture and process with my own S30 Pro.