Learning paths
Each path is a short route through the simulations and articles, ordered so that every step uses the one before it. Pick the question you are curious about and go from the top.
- 01 The Earth, Sun and Moon clockwork Seasons, phases, eclipses and tides: four everyday effects that come from three bodies and two tilts. 5 steps · 4 simulations
- 02 Gravity and motion, from a thrown ball to a planet Projectiles, pendulums, weight and orbits all come from one law of gravity. Climb from a ball to a planet. 5 steps · 5 simulations
- 03 Rockets and Mars, from the launch pad to a new world Why orbit is hard, how long Mars takes, whether anyone could live there, and how to live in a spinning ship on the way. 6 steps · 4 simulations
- 04 Relativity, from time dilation to the twin paradox Moving clocks run slow. Follow the idea from cosmic-ray muons to a twin who comes home younger. 5 steps · 2 simulations
- 05 Light and quantum, from bending rays to the double slit Light bends at a surface, spreads through two slits and changes when you watch it. Three steps from rays to waves to quanta. 5 steps · 2 simulations
- 06 Stars and scale, from the Sun to a neutron star How big things are, what happens if you swap the Sun, how far a star can be squeezed, and what decays inside. 6 steps · 5 simulations