Occasional paper: The edge of the galaxy and the end of everything

So there was a modest puff of articles last month about astronomers discovering “the edge of the galaxy”. They were referencing this recent paper, which… doesn’t really say that. But it’s an interesting paper anyway, so let’s discuss.As we all learned back in school, our Sun is one star in the Milky Way galaxy, which is a flat spiral containing several hundred billion stars. And spiral galaxies don’t exactly have an “edge”. We can’t see the details of the Milky Way, because we’re inside it. But we have excellent photographs of thousands of other spiral galaxies, and they mostly sort of gradually blur off into intergalactic space.So if you travelled outwards from Earth, away from the center of the Milky Way, there wouldn’t be any sudden cutoff where stars just stopped. Stars would gradually get further and further apart. At some point, there wouldn’t be any stars anywhere near you. But there wouldn’t be any “edge” as such. No glowing purple force field — — or golden pillars or…