I’ve always been interested in astronomy, although it’s hard to observe the skies in a suburban environment due to the light pollution. But even though I can’t see that much, I know there’s a lot more out there than literally meets the eye.
Our local address is in the Milky Way galaxy, and you’ve probably heard there are literally billions of others. But their spread across the sky is not uniform. The Milky Way is one of over 54 galaxies we call the Local Group. Three of these are large — Andromeda (the biggest), our Milky Way (second biggest), and Triangulum. The others are dwarf galaxies mostly clustered around the three larger galaxies. In terms of scale, the Local Group is about 10 million light-years across.
Astronomers don’t stop there; our Local Group is on the outskirts of the Virgo Supercluster of at least 100 galaxy groups and clusters with an estimated diameter of about 110 million light-years. The next classification is the Laniakea Supercluster of perhaps 100,000 galaxies extending over some 520 million light-years. And there are many such superclusters.
So if you’re fortunate enough to have a good view of the Milky Way, there’s a lot more like it in our celestial neighborhood.
Taken from “What is the Local Group?” ( https://earthsky.org/astronomy-essentials/galaxy-universe-location? ). The photo came from that website.