Dwarf galaxy

About

A dwarf galaxy is a small galaxy containing anywhere from a few thousand to several billion stars, making it significantly less massive and luminous than large spiral or elliptical galaxies like the Milky Way. These compact stellar systems are among the most abundant galaxy types in the universe and are often found orbiting larger host galaxies as satellite companions. In astrophysics and cosmological research, dwarf galaxies serve as critical laboratories for studying dark matter distribution, early universe star formation, and galactic evolution, since their small size and relatively simple structure make them easier to model than larger systems. When dwarf galaxies interact gravitationally with larger neighbors, they can be tidally disrupted, producing stellar streams — elongated trails of stars stripped away by gravitational forces — that reveal details about the host galaxy's gravitational potential and merger history. Understanding dwarf galaxies matters because they represent fundamental building blocks of larger galactic structures and provide observational tests for cosmological models predicting how galaxies form and grow over cosmic time.