We know less about the structure of our own galaxy than we do about many nearby galaxies like Andromeda. We literally can't see the forest for the trees because we are embedded inside our own galaxy, and interstellar dust blocks our view.

It's clear that the Milky Way has a structure like those, but it's hard to tell being in it.

There are at least as many galaxies in our observable universe as there are stars in our galaxy.

These are very normal, nearby elliptical galaxies that they studied, and if those galaxies don't have dark matter it calls into question the whole theory of cold dark matter.

We find active Super Massive Black Holes at the centers of massive galaxies. Our Galaxy also has its own black hole at its center measuring 2.6 million solar masses. Our black hole is not active today, but we presume it was active in the past.

I don't think I'm from this galaxy at all. I believe I came from the Andromeda galaxy, not so far, but far enough. Maybe that's why I'm an outcast.' He drew the spiral of Andromeda close to the Milky Way, almost touching. Then he pointed to Andromeda in the night sky above us.

'Maybe that's where I'm from too,' my father said. We could still see the stars.