A playable history of changing models

Cosmic Clockwork:
Rebuilding the Universe

The sky never changed its rules. Our explanations did. Carry one model across fifteen centuries as observations force circles, centers, ellipses, telescopes, and gravity to earn their place.

c. 150PtolemyPredict with epicycles
1543CopernicusMove Earth from the center
1570s-1601TychoMeasure before telescopes
1609-1619KeplerLet the circle go
1609-1610GalileoPoint a telescope skyward
1687NewtonExplain the clockwork

Kepler and Galileo worked at overlapping times. Scientific progress is a conversation, not a single-file parade.

Class identifier Use the identifier your teacher expects. Avoid entering your full name.

About 15 minutes • Touch, mouse, or keyboard • Pass 5 of 6 checks for a verified badge

History without the hero myth

Field notes

The game simplifies a long, international history. These thinkers did not replace one another in neat turns. They inherited mathematics, instruments, observations, arguments, and ideas from many named and unnamed people.

Ptolemy's Earth-centered mathematical model was sophisticated and useful for prediction; it was not simply “people being foolish.”
Copernicus placed the planets around the Sun but retained circular motion and epicycles.
Tycho produced exceptionally precise naked-eye observations while advocating his own hybrid Earth-centered model.
Kepler used Tycho's Mars data to develop elliptical orbits and variable orbital speed.
Galileo's observations of Jupiter's moons and the phases of Venus undermined key claims of older geocentric systems.
Newton's laws of motion and universal gravitation explained the physical cause behind Kepler's mathematical patterns.

NASA: Planetary Motion - History of an Idea NASA: Orbits and Kepler's Laws NASA: Galileo's Phases of Venus NASA: Gravity and Mechanics

Cosmic Clockwork:Rebuilding the Universe

Architect of the Heavens

Cosmic Clockwork:
Rebuilding the Universe