Galaxy
That is a galaxy.
Galaxy
a galexy
No, a nebula is not a galaxy. A nebula is a cloud of gas and dust in space, while a galaxy is a collection of stars, gas, dust, and dark matter held together by gravity. Galaxies can contain nebulae, among other structures.
A vast collection of stars is called a galaxy. Galaxies are massive systems that contain stars, planets, gas, dust, and dark matter, held together by gravity. The Milky Way is an example of a galaxy that contains our solar system.
A very large system of stars held together by gravity is called a galaxy. Galaxies can contain billions to trillions of stars, along with gas, dust, and dark matter. They come in various shapes, such as spiral, elliptical, and irregular. Our own Milky Way is an example of a spiral galaxy.
Bob
If they form a galaxy, it's called a galaxy of course.
Gravity
The answer is simple: gravity.
A system of billions of stars held together by gravity is called a galaxy. The one we live in is called the Milky Way galaxy.
Gravity basically makes things come together, and keep together. For example, due to gravity: * Galaxies form and keep together * Stars form and keep together * Stars get hot enough for nuclear fusion to start * Planets form and keep together * Planets keep around their stars, instead of wandering off into space