We think of galaxies as ancient. Our own galaxy, the Milky Way , formed 13.6 billion years ago, and the James Webb Space Telescope has allowed us to peer back to some of the first galaxies in the early universe.
But are galaxies still being born today? It's a fun question to tackle because it lets us dig into the messy, complicated, beautiful process of galaxy formation . Let's take a look at the possibilities. First answer: No Galaxies are pretty easy to identify.
They are large collections of stars, gas and dark matter. They are largely distinct from one another; a typical galaxy is roughly 100,000 light-years across, while the typical distance between galaxies is roughly 1 million light-years. Sometimes, galaxies merge or clump together inside clusters, but with a few exceptions, we can largely separate one galaxy from another.
They're like towns in the countryside: The distance between towns is larger than the towns themselves, so they're easy to spot and define. Sometimes, towns bump up next to each other, and sometimes, a sprawling city consumes its neighbors. But by and large, a town is just a town.
Related: Did monster black holes or galaxies come first? The James Webb Space Telescope may have a surprise answer Defining the start of a galaxy, however, is a different matter. Galaxies emerged in the early universe through a gradual process starting all the way back in the first second of the Big Bang . At that time, tiny pockets of higher-than-average density emerged an.