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.
Scroll for information about the object, and how I processed the data
M31 Andromeda Galaxy
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
Continuing to use PixInsight which is the premium paid software for stacking and image processing. The result was pretty good despite it being a while since I last captured, so I had to re-familiarise myself with the tool.
I did try the latest update to Stacking Wizard and Astro Wizard, which are free tools with a lot of hype. The advent of AI coding means these expensive tools are at risk, but I still find the free alternatives don't do quite the same job. So sticking with PixInsight for the time being.