Physics
Light, time, and the rules that hold no matter how you are moving.
What the universe is made of
Ordinary matter makes up about 5% of the universe’s total mass and energy. The visualisation follows that share into smaller categories, showing where stars, planets and other familiar objects fit.
How stars die
What a star leaves behind is fixed almost entirely by what it weighed when it was born, and the heaviest ones leave nothing at all.
The anatomy of a black hole
Whatever falls into a black hole, all that survives of it is a weight and a spin, and those two numbers fix every layer of the thing left behind.
What you can see and what you can change
Light takes time to travel. This limits how soon we can learn about a distant event, and how soon anything we do can affect it. A light-cone diagram helps us explore both.