Spacecraft Thermal Balance in Orbit

Every orbiting spacecraft lives on a knife-edge between overheating in sunlight and freezing in the planet's shadow. This simulator models that real energy balance in 3D: a satellite orbits a planet while absorbing solar irradiance (scaled by its absorptivity and sunlit cross-section) and radiating heat away by the Stefan–Boltzmann law (scaled by its emissivity and surface area), with power cut to zero the moment it enters eclipse. Adjust orbital altitude to change the orbital period and eclipse duration, absorptivity and emissivity to model different thermal coatings, and thermal mass to see how structural heat capacity smooths or sharpens the temperature swing — watch the live temperature readout and satellite color track the balance orbit after orbit.