Circumstellar Habitable Zone Simulator

This simulation couples a symplectic Velocity Verlet gravitational engine with a zero-dimensional energy balance model to dynamically calculate circumstellar habitable zones between the 340 K moist greenhouse limit and the 273.15 K freezing point. Users can actively manipulate key physical parameters in real time, including planetary semi-major axes, orbital eccentricities, stellar luminosity, and atmospheric albedo, to observe how thermal equilibrium shifts across different orbital configurations. To visualize how stellar evolution alters these boundaries over cosmological timescales, the software incorporates dedicated main-sequence presets. Cycling from a young, faint Zero-Age Main Sequence (ZAMS) star where the habitable zone contracts inward, to the stable G-type solar baseline, and finally to an advanced red giant phase, clearly demonstrates how rising stellar luminosity displaces the habitable zone outward and eventually boils away inner worlds.