Today in my general relativity class I got to talk about my favorite SUPER WEIRD COSMOLOGY FACT which is that if you have galaxies of the same size at different distances, beyond a certain distance, the farther away the galaxy is the BIGGER it appears in the sky (!!!)
If you want to dig into the math, you can look up "angular diameter distance", which is essentially a measure of how far away something appears to be based on how big it looks, and you'll find that ang. diam. distance only increases to a certain point, and then it goes down again
The intuitive reason that the most distant things look weirdly large is that the light we're seeing from them is from so long ago that the universe was MUCH smaller back then, so they were actually MUCH CLOSER and therefore covered more of the sky than you'd expect.
It's incredibly useful for astronomers that this effect occurs, because it means that we can see details in distant galaxies that would just be single pixels if the universe worked in a more sensible way. Cosmic expansion FTW!
Here's the very sciencey diagram I included in my book (#EndOfEverythingBook) to illustrate the concept of how a galaxy of the same size would start to look bigger again at a large distance. There's more discussion of it, and several other deeply trippy things, in Chapter 4. 
When I was learning astronomy in college/grad school I had a couple classes where angular diameter distance came up and the prof was like "oh & there's this unusual thing where it turns over" and I was all 🤯 and they just carried on like nothing happened and no one was screaming
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