Galaxies are vast systems of stars, gas, dust, dark matter, and other celestial objects bound together by gravity. They serve as the building blocks of the universe, containing billions to trillions of stars. Galaxies can range in size from a few thousand light-years across to over a hundred thousand light-years. They form the cosmic structures of the universe and are often found in groups, clusters, or superclusters.
Galaxies play a critical role in cosmic evolution, as they are the environments where stars form, live out their lives, and die, contributing elements to interstellar space that enable the creation of new stars and planets.
Types of Galaxies
Galaxies are classified based on their shapes, structures, and characteristics. The main types include:
