How are galaxies, clusters, and nebulas different?

It's very rare but a star can be created outside a galaxy. I don't have any examples but they exist and it's rare.

There are a ton of extremely powerful telescopes both here on Earth and in space that is capable of looking billions of light years far. And we can see a...

Most galaxies have a supermassive black hole at their centres. Most galaxies have little material falling into the black hole. Young galaxies and galaxies which have collided with others have...

When things fall to the ground, they are picking up energy from the gravitational field. In the case of Earth the gravitational field is modest but still offers enough energy...

Galaxies early on in their lives are actively forming hot, new stars and appear more bluish. Older galaxies are forming fewer new stars and their constituent stars are older on...

A few galaxies are bright enough to see something of them with the naked eye. For example, in the northern hemisphere we can see the centre of the Andromeda Galaxy...

From recent discoveries of astronomers, they have found out that dark matter is responsible for , and dark energy fuels the dark matter. But dark matter and dark energy are...

It is thought that most large galaxies have a supermassive black hole at their centre. Regular galaxies have relatively little material in the vicinity of the black hole and hence...

A nebula is a cloud of gas and dust, mainly hydrogen. They can be formed by gravitational collapse of interstellar medium which is mainly hydrogen and helium. A nebula can...

When a star which is less than about 8 solar masses runs out of Hydrogen in its core, the core collapses and Hydrogen fusion starts in a shell around the...