I find it fascinating that it’s unlikely that any of the “stuff” in the galaxies will actually collide during the merger because of the vast distances between the stars in the galaxies. Lots of stars will get ejected out into space and become rogue stars, though.

They join! It will take hundreds of millions of years, but they will merge into a single galaxy. Our galaxy will do this with Andromeda in about 4.5 billion years

I'm an astrophotographer and amateur astronomer

yes