What is a galaxy?

A galaxy is a vast, gravitationally bound system that consists of stars, stellar remnants, gas, dust, and dark matter. It is a basic unit of the universe that contains billions to trillions of stars, as well as planets, asteroids, and other celestial bodies. These celestial objects are held together by the force of gravity and rotate around a central point known as the galactic center.

There are three main types of galaxies: spiral, elliptical, and irregular. Spiral galaxies, like the Milky Way, have a disk-like structure with arms that spiral out from the center. Elliptical galaxies are more rounded and have a smooth appearance, while irregular galaxies have no discernible structure.

Galaxies are distributed throughout the universe and can be found in clusters, which are groups of galaxies held together by their mutual gravity. The universe contains billions of galaxies, each with its own unique features and characteristics.