Interactive Simulations

Hands-on labs with documented equations, assumptions and reset controls. Canvas-based, so they work on phones, with text results always visible.

Solar System Explorer

Select planets, play/pause orbits, change speed. Illustrative, not to scale.

Spin Earth from 0× to 10× and watch day length, speed and effective gravity change.

Move the Moon closer or farther: period, apparent size, light time.

Pick a planet, enter your mass, see your real weight there.

How long to the Moon, Sun, Proxima Centauri — at light speed or Voyager speed?

From a human to the nearest star, on one slider.

Side-by-side radius, mass, gravity, year and temperature.

Change eccentricity and see orbits stretch from circles to comet-like ellipses.