When I was looking at the jellyfish at the aquarium, I was thinking about how they are a surface like curved space time. Then I noticed that their shadow was being projected onto the surface below. The idea of projecting a multi-dimensional object onto a space of lower dimension is a good mathematical trick employed in many areas of Physics. Then I noticed that the APOD was called the Jellyfish Nebula. What could be better?
https://apod.nasa.gov/apod/ap190307.html
