Using the visualizations
How the interactive visualizations work: playback controls, sliders, keyboard and touch use, and the kinds of visualization you will meet.
Last updated October 11, 2026
The visualizations are part of each editorial's argument. They work on a phone: nothing depends on hover, and every control can be used by touch or keyboard.
Playback controls
Most visualizations share one control bar:
| Control | What it does |
|---|---|
| Step back / Step forward | Move one step at a time. |
| Play / Pause | Run the visualization automatically. Nothing plays until you press Play. |
| Reset | Return to the starting state. |
| Scrub slider | Jump to any step, or any moment in time. |
A short label beside the controls shows where you are, for example "Step 3 of 8" or the elapsed time.
Sliders
Sandbox-style visualizations expose their key quantities as sliders, such as the launch angle of a projectile or the eccentricity of an orbit. Drag a slider, or focus it and use the arrow keys, and the picture updates.
Keyboard use
- Tab moves between controls, and the focus ring shows where you are.
- Space or Enter activates a button.
- On a slider, Left / Right (or Down / Up) change the value by one step, Page Up / Page Down by a larger step, and Home / End jump to the minimum or maximum.
The kinds of visualization
| Kind | What you can do |
|---|---|
| Graph / array stepper | Step through an algorithm on an array or graph, with pointers, highlighted cells and a one-line note per step. |
| Trajectory sandbox | Change the launch speed and angle and watch the path. |
| Orbital sandbox | Change eccentricity and mass ratio and watch the orbit and a schematic transit light curve. |
| Composed scene | A custom scene built from reusable shapes, curves and labels, with optional sliders and steps. |
| Programmable scene | A custom scene driven by a small sandboxed program, built visually from blocks. |
The last two are authored without writing code. If you want to make your own, see The scene builder.
If a visualization does not load
Visualizations load after the page itself, so you may see a placeholder for a moment. They need JavaScript, but the text of the editorial, including the full proof, is available without it. If a visualization shows a configuration error, the editorial's setup is wrong, so please report it.