Just for fun and self education, I’ve built this over a weekend to teach myself why orbits exist, not just show planets going around. Something that was never clearly explain to me in school. It opens with a guided tour that builds the idea up step by step: two bodies and the equal/opposite force, inertia (the Sun is removed and Earth just drifts straight), then “an orbit is falling and continuously missing,” cosmic velocities with a little rocket, Voyager 1 & 2’s real gravity assists (the clock…
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