☄️ Comet Orbit Lab: Kepler Ellipse, Perihelion Heating and Sublimation — 2D Orbit Plan and Energy Balance

2D companion of the comet orbit lab: top-down orbit plan, distance and speed over one revolution, sub-solar temperature, water-ice sublimation rate and the sunlight energy balance, using the same Kepler solver and surface model as the 3D page.