My understanding is that it's not just the apparent size of the moon to its sun, it's that the window only exists for a while. So for this to happen on our plan

My understanding is that it's not just the apparent size of the moon to its sun, it's that the window only exists for a while. So for this to happen on our planet, and right now, means we're super lucky. Talking about coincidences; there's another interactive on the site that visualises how much of different precious materials may exist throughout the universe. And you're right, wood is one of the rarest.