Abell catalog

The Abell catalog is a collection of over 4,000 galaxy clusters identified by astronomer George Abell in the 1950s. Galaxy clusters are vast groups containing hundreds to thousands of galaxies bound together by gravity. Abell's work systematically listed these clusters based on their brightness and density, helping astronomers study the large-scale structure of the universe. The catalog provides a valuable reference for understanding how galaxies are distributed and evolve over cosmic time, offering insights into the universe's overall composition and the role of dark matter and dark energy within these massive structures.