Build a solar system

Predict, change, run, and discover what gravity really does.

Mission 1

Make one planet orbit

Ready. Make a prediction, then launch your experiment.

Orbit now

Nearly circular

Shape score e = 0

Year estimate

1 years

0 model days elapsed

On the planet

9.81 m/s²

Surface gravity uses real radius, not screen size

Model check

0% drift

Energy is staying consistent

Scientist note

A steady orbit balances inward gravity with sideways motion. Distances and planet sizes are redrawn to fit the screen; the calculations use real astronomical units.