This is largest photomosaic ever assembled from Hubble Space Telescope observations. It is a panoramic view of Andromeda galaxy (M31), the nearest galaxy to our own Milky Way, located 2.5 million light-years away.

Hubble resolves an estimated 200 million stars that are hotter than our Sun, but still a fraction of the Andromeda’s total estimated stellar population (~1 trillion, 10¹² stars).

The mosaic image is made up of at least 2.5 billion pixels, assembled from approximately 600 separate overlapping fields of view taken over 1,000 Hubble orbits. The full mosaic was carried out under two Hubble programs, starting with the Panchromatic Hubble Andromeda Treasury (PHAT) in late 2011 (Zoomable image), and followed up by the Panchromatic Hubble Andromeda Southern Treasury (PHAST)¹,

The PHAT program covered roughly one-third of the entire star-forming disk of M31 in six bands ranging from the nearultraviolet (NUV) to the near-infrared (NIR). The PHAST survey area extends the northern coverage of PHAT down to the southern half of M31, covering out to a radius of ∼13 kpc along the southern major axis and in total ∼two-thirds of M31ʼs star-forming disk, and images of approximately 100 million stars.

Here you can travel the galaxy with Bedřich Smetana’s Má vlast:

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1. Chen, Zhuo, Benjamin Williams, Dustin Lang, Andrew Dolphin, Meredith Durbin, Julianne J. Dalcanton, Adam Smercina, et al. «PHAST. The Panchromatic Hubble Andromeda Southern Treasury. I. Ultraviolet and Optical Photometry of over 90 Million Stars in M31». The Astrophysical Journal 979, n.^o 1 (enero de 2025): 35. https://doi.org/10.3847/1538-4357/ad7e2b. ↩︎