Dial in a planet's distance, speed and mass, hit launch, and hold its orbit inside the green habitable zone.
Adjust three sliders to set up your planet, then launch a deterministic gravity simulation that plays out in real time. A green ring marks the habitable zone; your score climbs the longer the planet stays inside it. A run ends if the system collides or ejects the planet, or when the time budget expires.
Worldsmith is an orbital-mechanics sandbox driven by a genuine N-body gravity model, letting you feel how gravity shapes orbits.
Setting up a planet with three sliders and running a deterministic gravity simulation, with a green ring marking the habitable zone, is orbital dynamics and stellar physics in one screen.
Scoring on how long the planet stays in the zone is the original objective.
Staying there is harder than arriving, which is the real lesson. The habitable zone is defined by where liquid water can persist, so it depends on the star's output and moves as the star ages — and an eccentric orbit can cross in and out of it every year.
Worldsmith is an original orbital-mechanics sandbox driven by a genuine N-body gravity model. It's free to play directly in your browser.