What is Galaxy?
Galaxy
A galaxy is a large system of stars, gas, dust, and dark matter, bound together by gravity. They come in various shapes and sizes and can contain billions to trillions of stars. Our solar system is located in the Milky Way galaxy.
Overview
A galaxy is a massive collection of stars, planets, and other celestial bodies held together by gravity. Each galaxy can contain millions to trillions of stars, along with gas and dust that can form new stars. They can vary in shape; some are spiral, like the Milky Way, while others are elliptical or irregular in form. Galaxies work through the gravitational forces that pull their components together, allowing them to form stable structures. The stars within a galaxy orbit a common center, which is often a supermassive black hole. For example, the Andromeda galaxy, which is the closest galaxy to the Milky Way, is on a collision course with our galaxy and will merge with it in about 4.5 billion years. Understanding galaxies is essential for astronomers as they help us learn about the universe's history and structure. By studying galaxies, scientists can gain insights into the formation of stars and planets, the evolution of cosmic structures, and the overall behavior of the universe. Observations of galaxies also provide clues about dark matter, which makes up a significant portion of the universe's mass but remains largely mysterious.