Comet Orbit (2D)

This top-down companion to the 3D comet orbit simulator strips the same real orbital mechanics down to a flat plane: a highly eccentric Kepler ellipse whose swept area stays exactly constant per unit time, with speed that visibly surges near perihelion and eases off near aphelion under the vis-viva equation. Two independent particle tails — a fast straight ion stream and a slower, gently curved dust stream — are spawned every frame along the Sun-to-comet direction, so the tail always trails away from the Sun and never gets confused with the comet's direction of travel, exactly as a real cometary tail behaves under solar wind and radiation pressure.