Physics, statistics, computing, biology and economics are what people say with it. Every planet is an idea someone invented to solve a real problem. Ideas of one topic orbit the same star; topics of one area form a galaxy. Glowing filaments show where one world borrows from another, and red planets on the outer orbits are problems nobody has solved yet.
Drag to rotate · scroll or pinch to zoom · click a galaxy, star or planet to go in · How Lumina works