The photomosaic of the Andromeda galaxy, created using images from the Hubble Space Telescope, took over a decade and features 200 million stars, a small fraction of Andromeda’s trillion-star population. Edwin Hubble’s discovery a century ago that Andromeda was outside the Milky Way galaxy transformed our understanding of the cosmos. Andromeda continues to provide crucial insights into the Milky Way’s structure and evolution, with NASA explaining its importance as a proxy for spiral galaxies. The Hubble Space Telescope, while not as new as the James Webb Space Telescope, remains essential to astronomy, capturing stunning images such as the detailed mosaic of Andromeda.
https://petapixel.com/2025/01/16/417-megapixel-andromeda-galaxy-panorama-took-over-a-decade-to-make/