The Andromeda Galaxy, also known as M31, is our nearest large galactic neighbor, lying about 2.5 million light-years away in the constellation Andromeda. This striking portrait combines broadband LRGB data with Hydrogen-Alpha (Ha) to reveal not just the classic sweeping spiral structure but also the delicate reddish glow of HII regions scattered throughout the galaxy’s disk. These Ha regions highlight zones of active star formation, most prominent in the spiral arms, where cold gas and dust collapse into new stars.

Data for this image were collected from two sites in Poland: Kraków and Lublin, under varying conditions that required careful calibration and integration. The total exposure time amounts to approximately 80 hours, allowing for an exceptionally clean and detailed view of both faint outer structure and fine internal features. The small elliptical galaxy M32 can be seen just above the bright core of M31, while the larger, fuzzier companion M110 lies below the disk, slightly offset.