Question

A galaxy contains large groups of stars, planets, gas, and dust. This matter must be held together, or the galaxy will break apart. What is responsible for holding the stars, planets, gas, and dust together in a galaxy?

Answer 1

The main force responsible for holding the stars, planets, gas, and dust together in a galaxy is gravity. The gravitational attraction between all the matter within the galaxy keeps it cohesive and prevents it from breaking apart. The mass of the stars, gas, and dust generates gravitational forces that act on one another, allowing the galaxy to maintain its structure. Additionally, dark matter, which makes up a significant portion of the total mass in the universe but does not emit or interact with electromagnetic radiation, also contributes to the overall gravitational influence within galaxies, further enhancing their stability and cohesion.