Moons - Explain to me like I’m a child

Ok, I feel like I am the only person who hasn’t picked up on these. A few months ago I opened my vault and I have commented on a couple of posts in this community, but I am still showing as having earned no Moons. I haven’t been too active, but I have liked a few posts, added some comments. Not an amount to make me think I should have earned a full coin, but maybe have a counter somewhere saying I have earned 0.001 of one? What action contributes to earning a Moon? What am I missing?

Let me know if this is the wrong forum and will move if required.