Not to scale. Orbits show eras, not real distances.
How to read this orbit map
- Glowing ball in the middle, labelled "Gravitational field": the topic that every idea on the map tries to explain.
- Coloured rings (orbits): one ring per era. The innermost ring is the oldest era (Era 1), the outermost is Era 6. The outermost ring ripples to remind you of gravitational waves.
- Small shiny balls (planets): one discovery, model or experiment each. Its colour matches its era ring. Planets sit on their ring in time order and slowly go round. Inner rings go round faster, like real planets.
- Small white ring around a planet: you have already opened that card.
- Labels: a name is hidden if it would cover another name. Point at a planet to see its name, years and one-line summary.
- Drag with the left mouse button (or one finger) to turn the whole system. Example: drag downwards and you look down on the rings from above, so they become circles.
- Mouse wheel or pinch to zoom. Example: roll the wheel forward and the planets come closer, so more names have room to appear.
- Right-drag or shift-drag (two fingers on a phone) to slide the view sideways.
- Click a planet: the camera flies to it and its card opens. The browser Back button brings you back here.
- Pause / Play stops or starts the revolution. Speed: move it from 1 to 3 and the planets go round three times faster; at 0 they stop.
- Era chips under the map: click one to turn the camera to that ring and list its planets. Click it again to show all eras.