Andromeda XXXV: New Dwarf Galaxy Discovery Challenges Galaxy Evolution Theories

Astronomers have discovered Andromeda XXXV, the smallest and faintest satellite galaxy of Andromeda, located three million light-years away. This discovery, detailed in 'Astrophysical Journal Letters' by Marcos Arias and Eric Bell from the University of Michigan, challenges existing theories on galaxy evolution, particularly regarding star formation duration. Unlike Milky Way satellites, which ceased star formation approximately 10 billion years ago, Andromeda XXXV continued forming stars until about 6 billion years ago, despite its small size of approximately 20,000 solar masses. Observations made with the Hubble Space Telescope revealed this galaxy's ability to sustain star formation despite the universe's re-heating phase, offering insights into the factors governing gas retention and star formation in dwarf galaxies.